Item Type: Flat Leg Spring Marking Gauge_x000D_ Product Material: Carbon Steel_x000D_ Maximum Opening: Approx.180mm / 7.1in_x000D_ Product Use: Circle on Wood, Plastic, Metal Surface, or Fast Copy of Processed Product Length 1Fine Adjustment: Equipped with a quick spring nut for quick and accurate fine adjustment. 2Material: Made of high grade carbon steel with hardened and finely polished tips. 3Durable: The flat leg structure makes the device very durable; it has a substantially hardened spring. 4High Hardness: Forged steel legs have hardened points for precise marking of workpieces. 5Adjusting Screw: With self locking washer and nut for quick and positive adjustment.1 x Flat Leg Spring Marking GaugePay attention to the front of the marking gauge sharply for protection.