It is short for basketweave.
Yes, any of the "775-83-13" magazine pouches will accommodate both Glock 17 and Glock 22 magazines. The biggest deciding factor is the middle part number of "83" which denotes that the pouch will accommodate the following firearm magazines:
Glock 17, 22, 34, 35
Heckler & Koch USP 9C, USP 40C, P2000 12-Round
Sig Sauer SP2340
Smith & Wesson M&P 9mm, .40
Smith & Wesson Sigma 9C, Sigma 40C, Sigma 9F, Sigma 40F, SW9V, SW40V, SW99
These pouches may accommodate the FN 509 magazines. Safariland has not provided fitment information for the FN509 so we cannot guarantee perfect fitment.
It will, but please be aware that most of the magazine will be sticking out of the top.
Yes, these pouches should also accommodate Glock 19 magazines.
Safariland recommends the "76" models for XD handguns. Here is an option:
https://www.opticsplanet.com/v/775-76-41-safariland-model-775-slim-triple.html
Safariland recommends the "775-76" models of their pouches for Beretta 9mm magazines. Here are a couple of those options:
https://www.opticsplanet.com/safariland-model-775-slim-triple-mag-pouch-stx-sw-59-ber-92.html
MPN: 775-83-13 will fit P320 9/40 magazines.
STX is Safariland's particular blend of polymer.