ITEM NAME:18V Lithium Battery PCM PCB Li-ion Protect Circuit Module Board DIY for Mak C8Y1 18V Lithium Battery PCM PCB Li-ion Protect Circuit Module Board DIY for Mak C8Y1 Lithium battery control circuit board Protection chip for electric tools battery Compatible With: For Makita Its main function to battery are: over charge protection, over discharge protection, short circuit protection, over current protection, reverse charge protection, over heat protection Color: Green Material: CCL Voltage: 18V Size: Approx. 4.5x3.3cm/ 1.77x1.3" Package Included: 1 x Module Note: Light shooting 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..1 x Module. Protection chip for electric tools battery.