Here is the 16inch, 420mm, inner barrel for silverback srs a1 fully upgraded kit. I switch from 16inch to 22inch barrel so I no longer need this setup. All the parts I used in this kit is brand new, besides inner barrel, but I already clean it. Whats in this kit -420mm inner barrel -fast hop chamber -fow nub -rhop -100% aireseal bucking, from faceless sniper -2 spare 100% bucking -1 spare rhop This setup has 100% airseal, and 100m ready or 328ft ready Buyer pays shipping, and price is negotiable. If u got any question do let me know.