Brakes, what is the 4 bolt thing?
It's for Magura HS33 hydraulic brakes. Normally they have an adaptor to fix them to canti bosses, but with appropriate mountings they can be bolted directly to a frame. This is more common in the world of trials bikes.
@Bearlegged started
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It's for Magura HS33 hydraulic brakes. Normally they have an adaptor to fix them to canti bosses, but with appropriate mountings they can be bolted directly to a frame. This is more common in the world of trials bikes.