IF 2nd Company Tac.Squad Sergeant (Daylight)

Hi! Love your colour scheme for the 2nd Company! I'm working on my own Fists army at the moment. They are a mix of several companies but I'm increasingly fond of the look for the 2nd. I was wondering about your black shoulder pads- is there any particular lore behind them or a personal preference. I ended up giving one of my sergeants the same look and I'm considering painting my Hellblasters with black pads as a throwback to the Crusade era Destroyers. In any case, I was curious if you knew of some lore source for black pads that I hadn't found- they look awesome in any case!