Halco 9116 R20FL100/S R20 100 watt 125 volt Medium Screw Base(E26) Halco Incandescent Light Bulb 100 Watts - 125 Volts Bulb Base : E26 (Medium) Bulb Shape : R20 Average Life (Hours) : 2,500 Length (In.) : 3.93 - Diameter (In.) : 2.48