Our Heavy Duty Custodian® is the ultimate in hydrant security. The operation is similar to the regular Custodian® but in an oversize configuration with thicker walls for instances that require increased protection. As in the standard Custodian®, the free-spinning armored housing completely protects the hydrant's operating nut and only personnel with the magnetic key wrench can open the hydrant. The special magnetic key wrench is designed to fit the larger dimensions of the lock. When your hydrant system needs the utmost in protection, the Heavy Duty Custodian can handle the job!