OP4050A, OP4015, OP4026, OP40201, OP40261, OP4030, OP40301, OP4040, OP40401, OP4050, OP40501, OP40601, etc. Compatible with Ryobi 40V Lithium Cordless Power Tools Model 1 Battery User Guide. Do not put battery into water and fire.
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