I bought these from eBay to fit to a post mount bike, which doesn't work! Below is a description from the Internet as I don't know much about them as I never got to use them. They do look decent brakes and the pads have plenty of life left in them too. The Promax Decode R brake caliper is designed for flat mount installation and is compatible with Shimano B-Series brake pads. It features a dual piston design for easy setup and effective braking performance, suitable for road and cyclocross bikes.
eBay