Shop › GEMTECH GM-45/BLKSD THREADMNT 5/8X24 GEMTECH GM-45/BLKSD THREADMNT 5/8X24 $80.75 Gemtech GM-45/Blackside Threaded Rear Mount Adaptor, 5/8X24 ThreadPitch, 300 Blackout 12194 Quantity: Add To Cart Added! Gemtech GM-45/Blackside Threaded Rear Mount Adaptor, 5/8X24 ThreadPitch, 300 Blackout 12194