Replacement Bulb for Commercial Grade String Lights, 11S14, 11W/130V, E27 Base, WHITE, Set of 20 Included  (20) 11S14, 11W/130V, E27 (medium) base, white glass light bulbs 11S14 bulb is recommended for commercial grade string lights 8,000 hour rated life Length  3 1/2, Diameter  1 3/4