Simply pump the bladder to your desired size and firmness, and press to deflate. We even included a second hose clamp as a secondary locking feature to insure air doesn't leak from your support while it is filled with air. Numerous strength tests have been conducted, including the final stage in which we had Matt jump on the filled bladder (which held up), before he proceeded to trip forward and nearly land flat on his face. Matt is 230 pounds, and has recovered from his injuries.