C9 Transparent Clear Incandescent Christmas Replacement Bulbs Great for outdoor lighting, string lights and Christmas lights These traditional C9 transparent Christmas lights are bright and and will provide many years of use for your indoor or outdoor Christmas light display. Our C9 7 watt, replacement bulbs will enhance your patio, roof line, Christmas tree or your home or business. The bulbs measure approximately 3" tall and 1 1/4" wide. The bulbs have an E17 intermediate base and work well with 25', 50' or 100' stringers (sold separately) or with custom applications. 25 Pack of Transparent C9 7 Watt Bulbs 3,000 Hour Long Lasting Bulbs 120 Volt 7 Watt Bulbs Indoor and Outdoor Use E17/C9 Intermediate Base Nickel Coated Base.