Pre-Assembled Valve Box Manifolds Our pre-assembled valve box manifolds take the confusion and headaches out of installing valves in your sprinkler system. It's already done for you! Save time! No cutting, re-cutting pieces cut too short or too long, or glueing to make everything fit just right. It's ready to go, just dig the hole, drop in the valve box and hook up the main and lateral lines. The lines are 1" Schedule 40 PVC and are mounted through the valve box for a perfect fit. No more trying to get the valve box to fit after installing the lines. Valve Box Measures 21" X 15 3/4" at the base. The pipes that extend out of the valve box already have 1" couplings installed to glue your lines into, no need to purchase more fittings. Also included is the valve box lid (not pictured), and 5 waterproof wire splices to connect the wires. Valves are 1" Hunter PGV valves. These are contractor/commercial grade valves, not the type you can buy at the local home improvement store.