4" XH Multi-Tite Rubber Grommet (PVC Schedule 40) - The Drainage Products Store
Amazon.com : HORTIPOTS 1/4 Inch Rubber Grommet Pack of 25 Top Hat, 6 mm ID Small Tophat Grommet for OD 1/4 Inch Vinyl Rubber Tubing in Hydroponic and Irrigation Systems (Pack of
Hillman 1/4 in. ID x 9/16 in. OD Rubber Grommets at Tractor Supply Co.
Hillman 1/4 in. Inner Diameter - 9/16 in. Outer Diameter Rubber Grommet 55054 - The Home Depot
Lot of 50 Rubber Grommets 5/16" Inside Diameter - 1/4" Groove - Fits 9/16" Holes | eBay
11/16 in_7/8 in Outside Dia, 1/4 in Inside Dia, Rubber Grommet Kit - 2MEV3|2MEV3 - Grainger