P&F Construction Corporation ordered 338 door units for an apartment condominium project from Friend Lumber Corporation. The doors were delivered to the job site three weeks after they were ordered.

Each door unit came wrapped in clear plastic. Three and one-half months after receiving the door units, P&F Construction notified Friend Lumber that the doors were one-quarter inch off size. P&F refused to pay Friend Lumber the balance due. What rule of law may Friend Lumber use to recover the money owed? P&F Const. v. Friend Lumber Corp., 575 N.E.2d 61 (MA).