Vintage Pyrex 77-C round glass replacement lid for Flameware glass coffee percolator. Marked in mold, PYREX (R), and 77-C with a batch code of D-6. Overall diameter 4.75", but the inner flange that sits inside the percolator rim is designed to fit a pot opening of roughly 4 inches, primarily the 4 Cup model, 7754. Clear glass with a small knob on top and two tabs on the underside designed to hold the lid in place while pouring. Vintage item in good condition, tiny pinpoint nick on one of the tabs, some scruffing/cloudiness on underside from normal use.