First Rate Boxing Speed Bag Platform Solid locking mechanism provides easy and effortless loosening and tightening of platform, and eliminates the possibility of accidental injury due to equipment failure 2" Acme threaded rod adjusts the speed bag platform incrementally to achieve your exact desired height This unique design is engineered in a cinder-cone shaped, solid aluminum configuration to evenly distribute the load The vibrating damper design keeps the wood platform completely vibration free. Fighting Industry approved! 2 inch solid poplar wood for lightning fast rebound bolts to16 inch on center studded wall or cement wall