Original DeWalt N912550 — spring (lock) washer designed for the blade/flange assembly on DeWalt cordless circular saws. The part is listed in DeWalt parts diagrams as a spring washer and sits between the inner and outer flanges to maintain axial preload and prevent looseness in the blade stack.

Common fitment: used on DeWalt DCS438 series (examples from parts diagrams include DCS438B, DCS438N and DCS438E2T — Type 1 assemblies), where replacing a worn or missing N912550 restores proper flange tension and helps eliminate blade wobble or excess play.

Small, inexpensive, and straightforward to install — a correct, original DeWalt spring washer that gets the saw back to firm, safe blade clamping without replacing larger assemblies.