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(2) TWO 40 watt-S11-Clear-Intermediate Base Bulb

Bulb size is 40S11/N clear S11N40

Base measures  5/8" Diameter or 17mm

Length is exactly  2 and 5/16 inches or 58mm

40 watt 130V household current

Used in Lava lamps, Old time high intensity desk lamps and Curio Cabinets

Heavy duty industrial grade made to last longer.

40s11, 40 watt S11, 40s11N