DAL 5040 Virtually Unbreakable Propellers for FPV Racing (Color: Black) 5040 size with 5mm shaft diameter works with most 250mm to 310mm mini quadcopters and hexacopters Virtually Unbreakable: Special Glass + PC Injection Holds up to most impacts. Won't snap or crack like other props. Pack Includes: 2 CW And 2 CCW Black propellers