1.It is used to repair and assemble batteries pack,2.only for people who are familiar with battery performance and have practical experience in battery assembly.3.Standard chip board PCB for replace for tools battery4.Replacement 40V Lithium-Ion Battery PCB Circuit Board For 40V OP4050A OP4015 OP4026 OP4030 OP4040 OP4050colour: greenMaterial: PCBsize: 15x6.8x3cmPackage Contents:2 x Protection BoardNote: This product is Charging Protection Circuit Board without battery core.Only the above package content, other products are not included.Note: Light 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.