The Bosch 28x1.8 O-ring is designed specifically for the 4th generation of Bosch Performance, Performance CX, Speed, and Cargo Line drives (model year 2020). It's an original Bosch spare part, ensuring a 100% perfect fit. This O-ring is essential when installing a chainring with the matching Bosch circlip. It protects the locking ring from loosening, even if the locking ring isn't installed precisely. Compatible with Performance Line Speed (BDU4XX) and Cargo Line / Speed (BDU4XX). Bosch Article Number: 1270016119.

Using this Bosch O - ring is easy. When you're installing a chainring with the matching Bosch circlip, simply place the O - ring in the appropriate position around the locking ring. Make sure it's seated properly for the best protection. As for maintenance, there's not much you need to do. Just check it regularly for any signs of wear or damage. If you notice the O - ring is cracked, worn out, or showing any other issues, it's time to replace it with a new one. Also, keep it clean to ensure it functions well. Remember, this is an original Bosch part, so using it as recommended will help keep your drive system in great shape.