Jabsco Twist 'N' Lock Pump Assembly For Jabsco Marine Toilets - New - SS23 Jabsco Twist 'N' Lock Pump Assembly For Jabsco Toilets This design uses a remodeled piston in the pump-out assembly. At the end of normal pumping out, at the bottom of the the pump stroke, the user simply turns the handle through 90deg and that locks the piston down onto the base outlet valve, keeping it securely shut.
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