Hard to source item now.

Converts frame or fork fitted with specific

four bolt Magura HS33 mounts

to accept standard Vee brakes.

This nifty little device was developed by Onza

as most of their Trial bike frames & forks were 

designed for Magura HS33 Hydraulic Caliper brakes.

Some people wanted to fit Vee brakes on them

so Onza solved the problem.

Requires 1 set per brake ie.

two sets per bike.