This double walled My Watersafe Heavy Duty Bladder is tough and versatile. This is a great way to transport 55 gallons of water or other liquid. The strong seals and tough bladder holds up to even rough handling. Fill the bladder in the back of your truck and roll it out on the ground. The My Watersafe 55-gallon bladder is one tough stand alone bladder. Included with each bladder is a hand operated siphon pump.