TruJumps's trampoline water anchor is the most effective way to secure your trampoline to the ground. The trampoline water anchor is designed and tested to hold your trampoline in winds up to 70mph. TruJump's water anchor comes in a set of 4 and they easily fill with water and straps around the leg pole of your trampoline. No more wasted energy and time trying to hammer an anchor into the ground, only to have it pull up and come loose out of the ground. One water anchor can hold up to 10 gallons of water and weigh up to 75lbs.