O-Ring Size Chart : The O-Ring Store LLC, We make getting O-Rings easy!
Performance Tool Metric O-Ring Assortment (419-Piece) W5203 - The Home Depot
Planet Eclipse O-Ring Finder App
Plastic Ring Size Finder Ring Sizer Ring Sizer 4 Through 12 - Etsy
CP Performance - O RING KIT Mercruiser 811612A3
O-Ring Gauge Make Work Smart, Telescoping O Ring Sizing Plastic Gauge, Slide Style National Type, for Measuring O Rings Inner Diameter, OD, Thickness Gauge Black: Amazon.com: Industrial & Scientific