The Spyre SLC is a mechanical disc brake that offers superior performance with incredibly easy setup. This is a dual-piston-actuated mechanical disc brake caliper that provides precise clamping force. This translates into even pad and rotor wear, because the rotor does not need to flex to one side during braking. We added a simple cable barrel adjuster to make fine tuning easy. All of this in an incredibly thin 40mm, 146g package that works with any drop bar levers on the market. Rotors and adapters are sold separately. For tandem bikes, we recommend the Spyre caliper paired with our 2.3mm thick rotors. This will give optimum stopping performance for you and your partner. SPECIFICATIONS - Weight: 146g per caliper - Carbon actuation arm for maximum rigidity, and weight savings - Dual-piston actuation - Works with ALL cable actuated road levers. Compressionless (linear strand) housing is highly recommended - TRP ultra-grippy semi-metallic pads. These are compatible with Shimano M525/M515 pads - Rotors, adapters, and flat mount mounting bolts sold separately - All flat mount calipers being mounted to the fork require the FF-5 Front Flat Mount 140/160mm adapter - Sold as a caliper only