RYOBI 21 in. Replacement Blade is the best solution for replacing your 40V Brushless Mower's dull or damaged. This blade is optimized for cordless mowers, improving cutting efficiency and increasing runtime. Buy with confidence knowing that this OEM part will work with your RYOBI 21 in. 40V Brushless Mower. Replacement part for: RY401140US and RY401160US.