SST. Sign is Maker Marked A.M. & Dated 1949. An outstanding example of this Tin Service Station Sign for Duplex Marine Engine Oil, a product of Quaker State Oil Company, Oil City, Pennsylvania. CONDITION: Sign shows excellent color & gloss throughout the field showing outstanding script with unique colors. Sign shows faint surface scratching in the field and retains all four of its grommets. The outer edge shows some very faint areas of paint wear but overall a brilliant example. Condition: (9.0). Dimensions: 20" x 10".