Rotary Evolution replacement blades are made of black etched carbon steel. The set contains 9 blades and the screws that go with them, so a blade change is done in one go without hunting for fasteners.
The set replaces Greenworks ARLM-9BL-GW, 2928207 and Cramer 2908686, 2916986 and fits Greenworks Optimow M, S, 4, 5, 7, 10 and 15, Cramer RM800-RM2700 and Cramer AiCONIC RTK.
Change all blades at the same time. A robotic mower runs with its blades balanced against each other, and a single new blade among worn ones makes the disc run unevenly.