Accumulator Tank - The Shurflo Accumulator Tank smoothes water faucet pulses and eliminates pump cycling to keep water line pressure up and pump motors cool. This will help to increase the life of your pump and even help save your battery power. Unlike other tanks, the Shurflo Accumulator incorporates a Butyl rubber diaphragm to help maintain pressure for months, rather than days and is pre-pressusrized to 30 PSI. Shurflo accumulator tanks are NSF certified. Attached mounting brackets. 24 oz capacity. 100 PSI maximum operating pressure. 1/2 inch NPT Male ports. Dimensions: 9.1 inch L x 4.8 inch H x 3.8 inch in diameter. 1 per package.