This is the same quad-section O-ring supplied as the inner seal with our External Shift Selector Finger Seal Kit (Part No. 1414). If your seal isn't sealing so well anymore, you may need a new seal.
We recommend fitting a new Replacement Wiper (Outer) Seal (Part No. 1416-001, sold separately) at the same time. The outer seal protects this seal from dirt. An old outer seal may allow some grit to get past and damage the new inner seal.
Note: This seal is only for use with the housing in our Seal Kit. Hewland bearing carriers were never designed for an oil seal. You must install our Seal Kit housing in order to use this seal.