20mm Picatinny Rail on Top
Design For Upgrade the Original Airsoft External Accessory
Package Include Charging Handle x1, T8 Quick Release Hop-Up System x1, Nylon Dust Cover x1, Receiver Pin x1, Mag Receiver x1, Safety Selector x1, Forward Assist x1, Trigger Box Pin x1
This hop-up system will have a flat hop-up wheel that requires a flathead screwdriver to adjust.

Length:    205mm
Material :     Aluminum
Weight :     600g
Compatibility: CYMA CGS series GBB  or  Tokyo Marui MWS series GBB