Paintball Grenade Launcher Tank Aluminum air chamber, paintball, Nerf rocket You get the Aluminum accumulator tank / chamber ONLY. This is to build your own Paintball, Airsoft, NERF rocket type launcher, fishing bait launcher, for Paintball, Airsoft, MilSim, or fishing. This is a high pressure DOT 3AL Cylinder that has been modified and adapted to be a Low Pressure (up to 140 PSI) Air Chamber or Reservoir. This refillable aluminum air chamber provides a safe alternative to using PVC or other plastics. Air chambers made from PVC or plastics are not allowed on most most fields, or public events due to insurance requirements.