Are These Capacitors Polyester or Polypropylene?

[dtm1962]

I picked up a pair of B&W Maxtrix 2 Series 1 and I was looking at the crossover and I had a question on the identity of these tan-coloured capacitors.

They PMT/2R type made by RCL.

View the photos and let me know if they are a Metalized Polyester or Metalized Polypropylene or ???

[Elvee]

Most likely mylar, unless it's a very early series (< seventies), in which case they are PC, but that's unlikely.

[AMV8]

Hi
I have a small pair of BW speakers and they use metalised polypropylene caps and they seem to be the same capacitors as in your crossover.
If your caps say PMT they are metalised polyproplyene capacitors.
Don

[Elvee]

Originally Posted by AMV8

Hi
I have a small pair of BW speakers and they use metalised polypropylene caps and they seem to be the same capacitors as in your crossover.
If your caps say PMT they are metalised polyproplyene capacitors.
Don

To my knowledge, ITT only used PC and PET for their PMT molded series.

Of course, you can find on Ebay such caps sold as PP, but it has nothing to do with what is really inside the capacitor: more with the seller's margins...

Here, an example of honest seller:
PMT/2R-1.5UF-100V Capacitors - 4 in stock to buy, photo, pdf datasheet, rfq, obsolete


And here, a candid or "misinformed" one:
2 PCS ITT-GB PMT/2R Molded Capacitor 2.2uF / 10% / 250V | eBay

For the average sucker it makes no difference since there is no simple and accessible way to tell them apart