Check the listing for details. Box of 25 ST40 Clear 7W C9 E17 Base Replacement Bulbs for String Lights. Color: Clear, Condition: New. Listed at 21.95 USD. Includes 1 Box of 25 ST40 CLEAR 7-Watt vintage light bulbs with C9 E17 base. ST40 bulb size is 3.25″ tall by 1.5″ wide, not including the C9 (E17) base, which is 5/8″ wide. 7-watt, E17 glass light bulb, 130 volts, Intermediate nickel base, 2700K. The average bulb life is 3,000 hours. For indoor and outdoor use. This unique light bulb is also dimmable! Compatible with all E17 C9 base light strings. Our ST40 clear light bulb creates a vintage style in a traditional incandescent bulb. These pretty bulbs provide the perfect brightness for decks, patios, backyards, restaurants, and large open spaces. Genuine Hometown Evolution, Inc. Product. We also have more styles like this! PS50 Clear: Item# 294040016763 ST40 Lantern Edison: Item# 303907182050 ST40 Mercury Gold: Item# 303904436637