Suppressor, silencer, flash hider, grip, heat shield, rail system, etc. then yes they are all gun or thread specific (i.e. 14mm CW/CCW). Although most M4 airsoft guns are the same or to spec, some are not. Find something you like, or are looking for and we can put you in the right direction.
ďREALITY IS LIKE A STONE. TO MANY ITíS HARD AND COLD, THEY CANíT HUG IT OR EAT IT, IT ONLY FRUSTERATES THEM AND DOESNíT DO THEM MUCH GOOD. TO OTHERS ITíS STRONG AND DEPENDABLE, YOU CAN BUILD WITH IT, BUILD UPON IT, OR WORK WITH IT, ALSO USE IT TO SMASH PEOPLE IN THE FACE.Ē