Commonly used on the pump body of AV pump range. These O- rings can also be used on the older Black ITT Marlow Argonaut pumps, but check which motor bracket you have.

AV Motor Brackets will have the number "4377800" and may have the letter "M" stamped onto the face behind the impeller. See Picture.

• Bracket with step uses O-Ring 4377800 (This listing)
• Bracket without step uses O-Ring 4377800M (Other listing)

Keep your O-ring in good condition by installing with a light coating of silicone grease