This is the o-ring that installs around the rear axle bearing before you put the bearing / axle assembly into the rear end. It seals the area around bearing to the inside of the axle housing and needs to be replaced each time you remove the axles to assure a leak proof seal. Danchuk # 19510 will work on any 1955-1956 classic Chevy with a stock rear end. Made in the USA. Sold in pairs.
Danchuk has the largest selection of quality 55, 56, 57 parts for your classic Chevy project.