Changes

A manual-pump head typically uses a foot pedal or handle to activate a manual pump to send the effluent to the holding tank. Manual pump heads are not dependent on electrical power, thus reducing the demand on the electrical system. They are very dependable and easier to install, and have relatively low maintenance costs. They can use seawater for flushing. Chief disadvantages are that users must learn how to use the pump (open the intake valve, select a dry or a wet position); users may not know if the flush is complete to the holding tank; and pipes can get clogged.

=== Electric Head ===