shimano gtx rx810 1x11 42t 172.5mm connecting rods are designed for different terrains and styles; they have a full chain line with 2.5mm for wider tires and greater distance from the frame. Single-platter connecting rods offer the simplicity of a single change on the rear cassette and feature shimano dynamic chain engagement profile teeth on the front chainring that provide more chain retention on rough terrain.Features:use : gravelmeasurements: 172.5 mmchainring: 42 teethcompatible with 1x11 speed drivetrain - hollowtech ii technology the hollowtech ii technology concept focuses on producing an excellent connecting rod set to maximize power transfer to the rider. The rigidity of the con-rod set guarantees pedaling efficiency, while its light weight, a key element of the con-rod set, enables the rider to improve performance over longer distances, durant which require more pedaling.