The Bullgear hop-up unit is the number one upgrade for CA/A&K compatible m249 airsoft guns. The Bullgear hop-up unit's hop-up lever is radically different from the original presser. In the Bullgear, the presser is in a horizontal position, just like in most other electric guns. The Bullgear hop-up unit corrects the problems caused by the original vertical presser and allows for an accurate and smooth thread for the bullet in the M249 model machine guns.
