Hi - I just bought a Sig Sauer 522 Classic yesterday after seeing a sale at Big- 5 and then researching the gun, and most love it. Of course I have all kinds of other rifles, handguns and shotguns too. I am just wondering what the 2 different Lego like looking pieces that came with the gun do?? They are like 2" long and came in a bag with the lengthened shoulder pad. Also what is the purpose of the button near the bottom of the rear of the stock that goes into a spring that goes into the buttpad - and you can move this backwards? Thanks - should be a fun gun Wanna kill these ads? We can help!