AMP RJ45 vs WE/SS (Regular) RJ45 Plugs

EDIT: As of 3Q 2021 it appears that all “AMP” plugs are very difficult to come by, with remaining stocks either limited or exhausted.

We’ve all heard that they’re different (somehow?) I thought this was going to be straight forward, turns out I was wrong.

Before we get into the details, we need to define what exactly an “AMP” plug is. In the first instance an AMP connector is made not by AMP, but CommScope. The AMP company was dissolved many years ago and its products have gone through various rounds of divestment and acquisition. Other brands this type of connector has been sold under (historically) are “Tyco” and “TE Connectivity”.

Non-AMP plugs are generally referred to as Stewart Stamping (SS) or Western Electric (WE) Style.

The second thing to consider is that eBay is awash with counterfeit products described as AMP plugs, but are not the products of any of the aforementioned suppliers, nor are they even physically similar to the genuine articles. Most of these are low quality SS/WE style plugs, and should not be used with AMP tools.

Suspiciously cheap AMP connectors for sale on eBay. Crystal? I generally prefer plastic. These particular ones aren’t similar to any CommScope plugs and would be destroyed if used in an AMP style tool.
A bag of 100 genuine AMP style plugs – CommScope branding. These connectors are made exclusively in the USA and should not be coming from China.

There are two distinct varieties of “AMP” (ish) connector.

  • Traditional or “Line” style (as their documentation refers to them)
  • “High Performance” style
Left: “Line” style connector (branded CommScope). Right: “High Performance” style connector (AMP branding). Which ever variety you are dealing with, if it doesn’t have the laser etched logo under the tab, and the two indents at the base of the tab, it’s counterfeit.
Left: “Line” style connector. Right: “High Performance” style connector. The high performance style is open inside, allowing the cable to be inserted all the way up to the contacts. More about that at the end of the article.

Example part numbers:

  • 6-557315-3 (Line style, round, 8P8C)
  • 6-569278-2 (High performance style, round, 8P8C)

Since you are here because of differences in tooling, let’s get straight into that. It turns out that these two require different tools:

  • 2-231652-1 (Black dot die) – Crimps “Line” style plugs
  • 3-231652-0 (White dot die) – Crimps “High performance” style plugs
AMP 3-231652-0 (1-853400-0 Die, white dot)
Left: AMP “black dot” die, Right: AMP “white dot” die

Which one is the fabled “AMP” connector? Both varieties are quite different to regular SS/WE plugs, however from a tooling perspective, the “black dot” tool for “Line” style plugs is significantly different. It is this type which other manufacturers sell tools labelled as “AMP” style.

For comparison with SS/WE I’ll be using the Stewart 2990003-01 tool (2990006-01 Die, yellow dot).

Stewart 2990003-01 (2990006-01 Die, yellow dot)
Left: AMP “black dot” die, Right: Stewart “yellow dot” die

When we look at the “black dot” die next to the one from the Stewart tool, the difference is clear. There is a third anvil in the centre which crimps part of the plug onto the stripped wire, a feature that no other type of plug has. Because of this, you cannot use this tool to crimp most SS/WE plugs.

6-557315-3 plug showing the extra “middle” crimp – specific to this type of connector

As for the “white dot” tool and associated “high performance” plugs, they’re not exactly the same as SS/WE plugs and associated tools but I’ve found that they are more-or-less interchangeable – I certainly could not see and problems with mixing them.

Left: AMP “white dot” Die, Right: Stewart Die

Since we’ve got all of this here – let’s put a clearly non AMP plug into the “black dot” die and see what kind of mess we end up with…

Non AMP plug crimped in “black dot” die

Not a great result, and unlikely to work very well.

But wait! Some non-AMP plugs are actually sort-of compatible with the “black dot” tool

A non-AMP plug, which has space for the wire punch-down

I would’t be making a habit of this. As we can see the wire has been damaged by plastic being squashed by the middle anvil. Not recommended!

The “high performance” feature

If you care enough to read on…

Left: AMP High Performance plug. Right: Standard “Stewart” style plug

On the left is an example of one, and on the right we’ve got the bog standard alternative. Please excuse the rubbish bit of wire I’ve used here.

In the case of the “high performance” plug the cable is butted right up against the terminals, meaning that there is only a minuscule amount un-twisted cable, whereas the plug on the right has quite a lot.

When we’re running long distances or at 10GbE this matters, but not in any other case.

In summary…

Some (line type) 8P8C AMP plugs crimp onto the cable at 3 points, whereas the rest crimp at 2 points.

I have only seen one other connector type which crimps at 3 points (also originally an AMP specific type – now CommScope) – a special variety of 6 position “long” modular plug which has the lengthwise dimensions of an 8 position plug.

853400-7 “violet dot” die from a 2-231652-7 tool with shielded and unshielded 6 position “long” plugs

These are normally used where a shielded 6 position type is required. Even without this requirement – if you are using 6 position plugs regularly these things are a heck of an improvement over the standard type. They fit standard 6 position sockets, crimp very easily onto round cable, and the longer dimensions and tab make them a lot easier to connect/disconnect.

Posted in Crimp tools and connectors

15 thoughts on “AMP RJ45 vs WE/SS (Regular) RJ45 Plugs

  1. My god, I think I’ve found my spiritual home. Stumbled across this site via Google and I have a lot of reading to do. I’ve been trying to explain to people (mainly network managers & technicians) for years about the differences between AMP/Commscope/TE Connectivity plugs and Stewart and other generic brands. I was going to try and explain the differences in a blog post, but you have done a much better job than I would have been able to!
    Thanks for a great article, I am now going to have a read of your connectors and crimp tools article. I don’t know why, but having the correct high quality tools and knowing how to use them properly is extremely satisfying, especially when you end up making a cable assembly that is as good as a factory one.

    1. > especially when you end up making a cable assembly that is as good as a factory one.

      About 9/10th’s of the reason why I splash out on these tools 😉

  2. I’m about to run out of 6-557315-3 plugs and I am having trouble sourcing them. RS, Mouser, Farnell, etc all say that they are no long manufactured, but the Commscope site does not seem to indicate this or list a replacement. I wondered if you happened to have a source or know of the replacement product?

    For years I have used an AMP 734218-3 for genuine plugs from years ago all the way up to modern Commscope branded ones. Recently I took the plunge and bought a 2-231652-1, because the old AMP tool is beginning to stick after 20 years of service and thousands of terminations. It is a lovely bit of kit, but a bit of a paperweight if I’m unable to find suitable plugs! 😀 Thanks

    1. Darn it. I was offered these at 5 bucks a bag of 100 last year. Would have bought a 1000 of them if knew they were discontinued.

      I don’t know how to get any more unfortunately.

      I noticed the boots were also discontinued last year too.

      1. Wow, you weren’t joking about expensive shipping, were you?! I have just ordered 200 from them and had them shipped to an address in the US for $15. My contact over there will then forward them on to the UK, hopefully at a much more reasonable price. I have an immediate need for only ~150 plugs and so if you’d like 50 I’d be more than happy to sell them to you at the same per-plug price I am paying once all shipping costs have been factored in and they reach the UK, hopefully without any additional import taxes!
        Hopefully you can see my email address as submitted with this form, drop me a line.
        I should have probably ordered more than 200, but if this all works out ok then there’s no reason I can’t order another few hundred later on.

  3. The “high performance” Cat5e connector 6-569278-3 uses a “load bar” that was placed over the end of the cable to keep the conductors aligned. Still listed on the Commscope web site.

    I have a kit with multiple dies for the 231652 tool. There are dies included for 4, 6, 6 long body, and 8 pin connectors. I have a list somewhere with all the available dies.

    Commscope has done odd things with distribution since acquiring the TE Connectivity product line. I have a friend at a distributor and will call in the morning to see what’s up.

    1. Look forward to hearing the result of that enquiry. Having all of the tooling for AMP connectors, only to find out they’re finished is quite frustrating to say the least. I’ve had a number of people contact me by emailing confirming this finding.

      1. I spoke to her this afternoon. She says they aren’t discontinued, but lead times are through the roof and it’s so much easier to get cheap Chinese connectors, that they aren’t selling very many of the AMP connectors. She has no stock on the 569278 (MP-88U-R) and only 113 pcs on the 554720 (MP-88U-F); one package plus 13 loose plugs.

        1. Oops… 569278 is the 5e “high performance” version (Commscope MP-5EU-_). 557315 is the MP-88U-R-_). Heilind has 23,000 pcs of the 557315. Avnet has over 1 million 554720.

          1. There are always those who don’t want / can’t purchase Chinese connectors. Interesting to see that they’re back in stock at Helind. UK Distributors are sticking to “discontinued” line for now it seems.

  4. Thanks a lot for a great writeup! Found this after learning the difference the hard way….

    I’ve been using an AMP “black dot” crimper with cheap eBay plugs for years without ever noticing any issues with it. Recently I discovered “slim cat-6a” (AWG28) cable, and got some matching plugs after giving up trying to align AWG28 with holes fitting AWG24. Crimping these plugs with the AMP tool failed spectacularily, causing severe deformation of the plug.

    Not understanding the problem, I was desperate enough to buy a cheap chinese crimper from a local store. And to my surprise – it worked flawlessly. Comparing the crimpers and the plugs revealed the differences you describe. I only wish I knew while I still had some hair left 😉

    Anyway, thank’s for writing this article. It’s always satisfying to understand why there was a problem, even after solving it.

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