In the words of BikeBiz:
"Another clever, simple workshop product from Birzman.
The Birzman Clam slides between the disc brake pads and the rotor for easy adjustment and alignment.
No more rubbing brakes, no more trial and error – instead, the Birzman Clam tool allows perfect pad alignment first time, every time.
The 58mm long, stainless-steel Clam comes in a three-piece set and retails for just £6.99."