Ridley Integrated Seatpost Clamps.
Generally speaking, Ridley ISP clamps come in a setback, or "race", version and a forward, or "TT", version. Each of these offerings is then available in standard height or extra high versions
All clamps come with a 5-piece spacer kit; with the following sizes: 1mm, 3mm, 5mm, 8mm, 10mm
Standard clamps allow for 17mm of saddle height adjustment; extra high clamps allow for 40mm of saddle height adjustment
ISP = Integrated seatpost