This mercury carburetor synchronizer tuner (carb synch tuner or manometer) has a sheet steel body with clear markings incremented every 2cm from 2 to 54 for simple accurate tuning and includes mercury vial, hose, line restrictors, 5mm (for Honda, Kawasaki and Suzuki) and 6mm (for Yamaha and many European motorcycle) adaptors and easy to follow instructions. By Barracuda Bike Parts™.