What is this?

[jah]

A couple of my newer W.E. 2500s have this little orange box/container inside.  Looks almost like a modification or repair but I have more than one like that so I guess it's factory standard for the later models.  My question is, what is it and why is it in some phones and not others?  Photos attached.

[Jim Stettler]

It is a polarity guard. (bridge rectifier)
Without it your TT pad wouldnt work if your ipolarity of the phone line got reversed.
Later phones had it built into the dial.
Jim

[jah]

Thanks Jim.

-Jeff

[Phonesrfun]

A couple of my newer W.E. 2500s have this little orange box/container inside.  Looks almost like a modification or repair but I have more than one like that so I guess it's factory standard for the later models.  My question is, what is it and why is it in some phones and not others?  Photos attached.

Adding to what Jim S has said, these polarity guards were not part of the original design of the Bell System Touch Tone phones.  Polarity on Touch tone phones is important, but when TT first came out, only Telco installers were supposed to be installing phones.  Those guys were trained to deal with polarity issues.

Leading up to the breakup of the Bell System, the phone companies were being compelled to sell the phones to the subscriber and allow them to install them by themselves using modular plugs.  Since polarity issues would have caused many do-it-yourself installations to fail and result in a service call, the polarity guard was installed on many phones after the fact, so customers would not have polarity issues when plugging in their newly purchased phones.

[Jim Stettler]

I used to get a lot of TT phones cheap at yard sales because it doesn't dial anymore.
Almost always it was a polarity issue.
Jim

[jah]

Leading up to the breakup of the Bell System, the phone companies were being compelled to sell the phones to the subscriber and allow them to install them by themselves using modular plugs.  Since polarity issues would have caused many do-it-yourself installations to fail and result in a service call, the polarity guard was installed on many phones after the fact, so customers would not have polarity issues when plugging in their newly purchased phones.

That makes sense as only my newer 2500s from the early 80s have it and it does look a bit like a modification.