This Maytronics Dolphin™ 9980364 Wave Main Locker for Dolphin™ Wave 300 is a reliable replacement part, designed to seamlessly intergrate with the original pool cleaning system. The main locker protects important components in the pool cleaner. Maytronics pool cleaners help keep your pool healthy and clean, which is of the utmost importance. Ensure that your pool cleaner is running as cleanly as possible with this certified genuine part.