product features: Double window scale,plastic grip,high precision,hard construction,resulting in fast and efficient operation. Head holders:9x12mm,14x18mm,,24x32mm or 27x36mm,accommodate variety of standard heads. +/-4% accuracy in clockwise direction exceeds international specifications. Ergonomic soft TPR grips are comfortable to use. Lock Knob secures selected torque from accidental change. Dual Metric and English scales are easy to read and set,fine increment operation. Want to know the size you need? Come visit our website now https://www.atwwren.com/products/REDUCER_Insert.html Or contact us Tel: +86 571 8811 5720 Fax: 0571-88110210 Postcode: 311100 E-mail:info@wrenchina.com Company Name: Hang Zhou WREN Hydraulic Equipment Manufacturing Co., Ltd. Address: No. 24, Xingxing Road, Linping, Hang Zhou, China