Gog Smart Parts Feedneck - Silver Airsoft Clearance Lightening the bolt means that

Lightening the bolt means that the marker will naturally have less kick/recoil as the bolt moves back and forth

V3 Changes:

Every barrel is even hand-checked for QC-- You can't get any more accurate

Two piece alignment is a critical factor in a barrel’s true accuracy

Gog Smart Parts Feedneck - Silver Airsoft Clearance Lightening the bolt means thatThe Q Lock solves all your hopper issues. Open the quick release lever, insert the hopper, hand tighten the thumbscrew and then close the lever. No tools needed. The Q Lock has an abrasive internal surface to securely hold any hopper in its place. The Q Lock is currently available for all Smart Parts markers. The Q Lock also fits most center feed Spyder and Piranha markers with an adapter.