On the subject of holsters, Israel's Fobus has been making holsters of many kinds for a long time. The first ones to really get popular were mostly passive retention, but they've since released a number of thumb-retention or trigger-lock style holsters. Most of the Fobus users I've known either loved or hated them. Mine held up fine back in the day (we're talking nearly 10 years ago) but I never wore it for anything but off duty carry and never really spent much time in extreme weather conditions so take that for what it's worth.
One of the newest holsters from Fobus is their first IWB style. It utilizes passive retention to hold the weapon, with an upper and lower retaining hook to keep it secured to a belt. This is the Fobus GLC. Current versions fit Glock models only.
Note: please do not troll and say these guys stole molded holster ideas from one of the current custom Kydex companies - Fobus, among others, was making injected molded polymer holsters before many of the current Kydex manufacturers graduated high school.) (which I personally prefer over the passive kind.)