TCN Skeleton Oil Seal Fits Excavator

Made by Sanping, a reputable oil seal supplier, the TCN oil seal is composed of rubber, metal skeleton and tension spring. It is generally installed in an open groove. When the oil seal is installed, it can overcome the rotation of the shaft under the action of the holding force generated by the contraction of the spring.
https://www.sanpingmachinery.com/products/tcn-skeleton-oil-seal/