Plate installs on water pump holes in block and allows the block to be pressure checked. If the cylinder head is installed then the block and cylinder head can be pressure checked at the same time. Kit comes complete with valve and gasket. A pressure gauge is optional. A torque plate is required to pressure check a bare block. The block should be filled with water when pressure testing to reduce the risk of injury and to help find any leaks. 30psi maximum pressure when testing! Too much pressure can ruin the block and may cause injury.