Little Giant Pump Replacement O-Ring Part# 924007
Fits 1-MD, 2-MD, 3-MD, 4-MD, 5-MD, 3-MDX, 3X-MDX, 2-MD-SC, 2-MDIX-SC, 3-MD-SC, 3-MDIX-SC, 4-MD-SC, 4-MDIX-SC, TE-4-MD-SC, TE-4-MDX-SC, 5-MD-SC, TE-5-MD-SC