Mueller Electric Blog

How to Select the Right Electrical Clip

Posted by Mona Weiss on Apr 11, 2018 8:23:21 AM

From electrical design to maintenance, engineers must determine what electrical clips (also called alligator or crocodile clips) are best suited for their project.

These clips can range from small to large, be made of a wide range of materials, come in various jaw types, handle wide ranges of electrical current and can be certified for safety by being UL-listed.

With such a wide range of options, there are many factors to come into play when selecting clips


Typically, electrical and electronic clips are rated by their ability to handle varying levels of current which is measured in amps so you will need to know the amount of current that you will be dealing with.

Once you know the level of current, you can calculate the amperage rating required for the clip.

The formula for Amps is Watts divided by Volts.

The amperage capacity of a clip is typically listed right on the clip itself.

Generally speaking, larger clips are able to handle more current, however, that doesn’t always mean a larger clip is always necessary. Solid copper clips are able to handle higher levels of current and carry a higher amperage rating than its zinc plated steel counterpart. For example, a heavy duty clip for battery and test work applications may be rated at 50 AMPS for the zinc-plated steel version while the same sized clip made in solid copper is rated at 100 AMPS. 



Clip Jaw Typesclip jaws4

Another factor to be considered is how the clip needs to connect to its point of contact. Clips come in all shapes and sizes with different types of jaws and teeth. Clip jaws can come flat nosed, with teeth, or wrap around a terminal or pipe. Some clips have flat wide noses with teeth and others may be rounded to grab round objects. Deciding which clip to use is dependent of what the clip is grabbing on to and will vary per application.

Flat nosed clips are typically used in paint grounding.

Smaller clips with teeth are used for test and measurement.

Larger clips that wrap around will provide a strong grip and may penetrate a layer of paint. These are often used for battery charging and grounding.

Flat wide jaws with teeth are perfect for grounding and work holding uses.

There are, however, a tremendous number of applications for all types of jaw styles. As technology progresses, so do clips, with new types being invented all the time.

For more on different types of clips and what they are used for, check out our guide to clips

Clamp Pressure

Clip grabbing strength, or clamp pressure, is another factor to take into consideration when selecting the right clip. Clamp pressure usually increases as clip and spring size increase. Larger clips will have a stronger grip than smaller clips. In some cases clips can be made to have less clamp pressure which can be helpful for delicate or detailed situations.

Clip Size

There are many different sizes of clips and size can sometimes be important to consider. One determining factor is if there is a space requirement. Another factor is the amount of clamp pressure required, as well as the amperage rating needed.

Some clip sizes are determined by the application itself as there may be limited space where the clip can fit.  Naturally if you have a small space then you probably will pick a smaller clip.

Higher amp rated clips tend to lend themselves to uses where a tight space is not a concern. The environment may dictate what a clip size may need to be as the larger clips tend to hold up better in harsh environments such as electroplating.

There is no real guideline on determining what clip size to use. Some engineers try to make sure they have the right amperage rating, clamp pressure and jaw type in the smallest package possible to reduce the possibility of “overkill” and inflating costs unnecessarily. Other engineers go one step up in size to ensure all bases are covered. In most cases, several different sizes of clips are used in various prototypes to test first hand which clip size is best.


3 alligator clips rectangle-1

Clips are made with zinc or nickel plated steel, stainless steel, solid copper, gold plating and even nickel-silver.

Generally speaking, zinc or nickel plated steel is the most cost effective material used in clips.

Solid copper clips can handle higher levels of current better than similarly sized clips made of other materials.

The environment where the clip will be used can determine what material should be used for a clip. For example, stainless steel clips can withstand marine, caustic or corrosive environment better than other materials. Other clips that can be used in marine environments are marine rated clips which are made of solid copper for greater connectivity but with moisture resistant springs which significantly extend the life of a clip used in the vicinity of water and salt.

We did an experiment to show how marine and stainless steel clips hold up compared to other clips. Read about it here. 

Read about different metal finishes for clips here.  


Safety is always a consideration when working with electrical components, but some more than others.

For instance, when using clips and cables for grounding and bonding, an exposed clip works just fine, while other applications it may call for an insulated clip.

UL Listed products are certified for safety. UL Listed clips and connectors are certified to insure that human hands cannot come in contact with the conductors while in use and energized.

Other applications may call for clips to be utilized in a “hands free” environment which means that the clips are not manipulated or touched while a circuit is energized. The clips still need protection from touching each other or other parts which could interfere with the electrical signal or cause a short, so insulators or “boots” are placed over the clips to protect them.

For help in selecting clips with different features, try our clip selector.

Topics: Test & Measurement, Static Electricity Grounding, Grounding, electronics, crocodile clip, engineering, alligator clip, Marine Clips

How Well Do Marine Clips Hold Up In Saltwater?

Posted by Mona Weiss on Mar 1, 2018 11:58:49 AM

When selecting a clip for an application, there are often environmental considerations that may affect the clips over time. One of the toughest environments is a marine environment where there is a lot of moisture and salt which corrodes many types of metal. 

I performed an experiment with our 46 series clips to see how well the marine clip actually withstands a salty marine environment. 

We already know that Stainless Steel and Copper both hold up in a marine environment pretty well, but how well? One of the primary uses for clips is for safety and electrical/grounding applications, so it's important that the clip holds up well and works the way it's supposed to. Clips that cannot hold up in a marine environment would need to be replaced often, which also adds a cost consideration. 

Stainless Steel and Copper are both excellent choices for a marine environment and the main difference when selecting a clip that is right for you would be if you need to solder to the clip. Stainless steel is nearly impossible to solder a wire to. Copper is easily solderable. In most cases the 46M (M for Marine) would be the clip of choice because of that soldering capability. 

Now onto the experiment!

The Setup:

I took 1 of each of the following clips and I put them in a plastic ziploc bag partially filled with with salt water to simulate a wet salty environment with both water and air. Salt water corrodes metal five times faster than fresh water does and the salty, humid ocean air causes metal to corrode 10 times faster than air with a normal amount of humidity.

I documented the changes in the clips over time with exposure to that environment. 

An introduction to the different clips taking part in this experiement:

BU-46A :  Copper Plated Steel with a Steel Rivet and Spring

BU-46C : Solid Copper with a Steel Rivet and Spring

BU-46X : Stainless Steel with a Stainless Steel Rivet and Spring

BU-46M :  Copper with a Stainless Steel Rivet and Spring

Note - these clips can also come with insulators. For the purposes of this experiment, none of the clips are used with insulators.  

Here's an image of the clips before they go into their salty environment - tops and sides. 

Clip Starting Lineup.jpg Clip Starting Lineup Tops.jpg

Day 0 (January 4th 2018): the clips were placed in their respective ziploc baggies with salt water. 

Day 1: There are some changes already! Baggies 2.jpg

The 46C bag shows green discoloration in the water from the salt reacting with the steel rivet, but the clip itself looks ok. The water in the 46A clip bag has taken on a slightly yellow tinge. No change in the 46M or 46X. 2 clips.jpg

 Day 5:

The bag with the BU-46C is pretty funky looking from the steel spring and rivet corroding. The BU-46A is also looking funky but not quite as much.  The BU-46M has a slight green tinge to the water as expected with copper, but the stainless steel rivets are not corroding. The BU-46X is looking fine!  

Clip Lineup Day 5.jpgbag lineup day 5.jpg

I took the clips out of their bags for a photograph. The two on top are the ones with the steel rivets that are corroding due to the salt, which is causing the discoloration that is coating the copper.  

 Day 8

Notice that 46 C appears to have less corrosion on it - that's because I photographed it lying on the other side. Since I have them lying on their sides in these baggies, the side with more air exposure seems to look worse. 

I also photographed them on their edge - the water line is more apparent. 

clip lineup day 8.jpg


You can also see the steel spring in 46-C is really starting to corrode. For comparison you can see the stainless steel spring in the 46M is holding up just fine. 

corrosion in spring of 46-C comparison1.jpg


Day 11

There's quite a bit going on in these bags. 46A and 46C have a lot of corrosion in the water. 46M's water has a green tinge from the copper, and 46X - the stainless steel one has clear water. 

Salt_bags_corrosion.jpgclip lineup Jan 15.jpg

Here's the clip lineup. The 46C has a ton of crusty corrosion on the side - this was the side that was in the water. It seems like the crust is coming from the rivet. Below is a closeup of the clip so you can see this corrosion. It's starting on the 46A but much worse on the 46C.  Compare with the stainless steel rivet on the 46M.

clip corrosion closeup.jpg



Day 14

Let's take a look at the bags. The reflection on the plastic makes it a little hard to read what's what. The top photo is the 46A and 46M clips. You can see the rust and corrosion in the water of the 46A. The 46M has a greenish tinge from the copper. 

The lower image is the 46C and 46X. The 46 C is also full of rust. No change in the 46X. 

clip bags.jpg

clip bags 2.jpg

Next, I took them out of the bags to photograph. The 46A has this black line going across the rivet - that's some crusty corrosion. 

clip lineup day 14 ss.jpg

Here's some up-close photos to look at the corrosion. 

First is the 46A - it appears that black crusty corrosion is coming right out of the rivet. It breaks off really easily. I have tried very hard to keep as much of it in place as possible but the slightest touch makes it crumble off. The spring inside is totally fused with rust. 

46 A corrosion side and back 2.jpg

Next is the 46C. There's so much rust and corrosion on the inside. This didn't take long to form at all. There's similar crustyness near the rivet that chipped off as I was removing it from the bag. 

46C corrosion.jpg

Next is the 46M. This is the copper with stainless steel rivet and spring. The outside actually looks rather pretty. It is starting to get a patina but it isn't crusty and gross. The spring and rivet are in excellent shape. 


I was a bad scientist and forgot to photograph the 46X up close - mostly because there's no changes at all. It looks the same as when I first put it in its bag. It is entirely stainless steel and isn't corroded. 

Day 18

Its getting harder and harder to keep the board clean that I'm photographing these on. When I remove them from the bags to photograph I have some paper towels that I use to gently dry them off, but even when they are decently dry, they will still leave a mess when they touch the white board. 

clip lineup day 18.jpg

Day 25

The 46C fell apart. When I went to take it out of the bag, the rivet was gone. 46 c corrosion.jpg

Of course now we need to take a look at the other springs more closely. On the left is the 46X, the middle is the 46M and the right is the 46A. It's hard to get a good photo with detail but the two stainless steel springs on the left are in great shape. The steel spring on the 46A on the right is rusted and fused together. 

clip springs.jpg

 Day 29

Here are our lovely bags!

bag lineup .jpg

There is no visible change with the bags - until I picked them up. I did notice that there was quite a lot of salt crusted on the outside tops of the 46A and 46C bags. 

The 46A rivet disappeared completely as it did in the 46C. One difference I noticed between the 46A and 46C bags is that the 46A bag feels more crusty/sludgy. It was really gross. There was black rusty crusty sludge all over the clip when I took it out. Total tetanus soup. I really did not enjoy taking it out of the bag, and toweling it off. The 46C bag is like that too but much more liquidy. 

clip lineup day 29.jpg

The remaining clips that both have stainless steel rivets and springs are in great shape. 

stainless springs 1.jpg


 And the two winners are the 46M Marine clip and the 46X stainless clip! Both have stainless steel rivets and springs so they won't corrode in salt water. While the 46X looks the same as it did when we started the experiment, the 46M has started to develop a patina on the copper. 

This green color is copper chloride, and is a layer of corrosion that forms in a saltwater environment, like on the Statue of Liberty. The other copper clips likely have this copper chloride layer as well, but there is so much other rust in the water it doesn't show up. 

Why choose the 46M clip over the stainless? As stated at the beginning of the post, the all-stainless clip cannot be soldered to, so if you need to solder a wire to the clip, you need something that can be soldered to. So while the 46M looks worse than the stainless, it still provides an added utility that the other does not. When selecting a clip, consider if soldering is necessary. If not then the 46X would be your best choice. If you do need to solder, the 46M is the best choice. 

For a more general overview of different kinds of clips, check out our Guide To Clips.



Topics: Marine Clips