V38-118 – Marine Pump Clamp Knob Compatible with American Marine, Ultra Flow, WhisperFlo Pre-98, Purex 2000 Series (pre-1998) and Wet Institute Pumps Height: 2 7/16″ Thread: 1/4″x 20″ Produced with the highest quality, heavy-duty materials to ensure long-lasting performance and efficiency.   **CA Residents See Prop 65 Warning