COLUMBUS Expander For Carbon Steerer can be used with most 1-1/8" carbon forks.
The expander plugs comes in these different variants:
40mm long expander.
60mm long expander.
60mm long expander with slit for internal dynamo cable routing.
COLUMBUS Tubi is a manufacturer of steel tubing used in bicycle frames. Located in Settala, in the Province of Milan. The company was founded in 1919 by A.L. Colombo and was taken over by Colombo's youngest son, Antonio, in 1977.