Specifications: Working temperature: 0℃-40℃ Display: capacity/ voltage Back-light: Green Product dimensions: 2.41 x 1.31 x 0.53 inches/ 61.3 x 33.3 x 13.5 mm Mounting hole dimensions: 2.3 x 1.12 inches/ 58.5 x 28.5 mm colour: black Material: ABS Package Contents: 10 x Battery meter Note: they cannot be applied for lithium iron phosphate batteries, 1-2 Li batteries in series and over 15 Li batteries in series. 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.