You can find all the spare parts and components you need at Escapa.
The Shimano GRX Chainring for FC-RX810-1 is designed to be compatible with the GRX FC-RX810 1x11-speed crankset.
FEATURES:
Mounting: 4-bolt
BCD: 151 mm
Teeth: 40T, 42T
Gears: 11-speed