This product is based on piezoelectric effect of artificially polarized ceramics. It is suitable for conventional vibration measurement of mechanical equipment, especially for rotating and reciprocating machinery. It can measure vibration displacement, velocity and acceleration, and is widely used in fields like machinery manufacturing, electric metallurgy and general aerospace. Functions:Full display; Screen flipping; Switch acceleration measurement between high and low frequency; high frequency (1KHz-10KHz) /low frequency (20Hz-1KHz) Curve display; Store and view files; Power indicator; Double measurement button; Flashlight; Screen brightness; Select Chinese/English; Shutdown time setting; Machinery grade; (Batteries are not included in the shipment, you need to bring 2 xAAA batteries) Color: As Shown Material: plastic Package Contents: 1set x digital vibration meters Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.