Ryobi P421 6500 RPM 4 1/2 Inch 18Volt One+ Lithium IonPowered Angle Grinder (Battery Not Included, Power Tool Only) Availability: In Stock. Product Features: Angle grinders are indispensable for a variety of jobs done around the house. From cleaning grout to clearing rust to cutting tile, nothing other than an angle grinder (or an expensive ...