MRC:
A feature of the item of supply which must be specifically recorded when the reference number covers a range of items.ZZZY
Reference Number Differentiating Characteristics:
Size 2-1/2 in. Valve kit consisting of, 2 - no. 2, gasket, cover plate, 1 - no. 3, spring, main valve, 1 - no. 7, spring, check valve, 2 - no. 9, disc, main and check valve, 2 - no. 12, disc, upper and lower relief valve, 1 - no. 14, spring, relief valve, 1 - no. 18, diaphragm /set/, 1 no. 20, gasket, clamp bolt, 1 - no. 23, gasket, relief valve housing