Ceta Form New T90 Ratcheting Bit Drivers. For high speed and accurate screwdriving. This new series, available in both stubby and full size versions, feature a very robust ratchet mechanism. This mechanism allows for a return angle as low as 8°. Moreover it can stand up to a torque level of 50 Nm. T90 Ratcheting Bit Driver has an ultra smooth ratcheting action thans to fine gears. With a retractable bit cartridge of 6 bits.