Part number: ALM CH057
ALM Manufacturing 57 drive link chainsaw chain
Suitable for the following Ryobi models with a 40cm (16") bar
ECW 1840,
RCS 3540C,
RCS 4040C2
Compares to N1C-BL-M-57E SK
NOTE
Check the suffix of your model number carefully as some models with a different letter at the end were manufactured with a 56 link chain