Regulatory buoys feature rotationally moulded high density polyethylene shells that are UV stabilized. The moulding process allows for uniform wall thickness without the internal stresses that cause cracking over time and under extreme temperature changes. This process gives tremendous impact strength to the shell. The shell thickness is 3/16" with closed-cell polyurethane foam inside. Danger #2 buoy - 48" x 24" (max.) - 235 Ibs. buoyancy