C9 Christmas light strings are bare E17 sockets on heavy-duty wire with bulbs sold separately, so you pick the bulb and the color and swap them later without replacing the whole string. Choose pre-sized stringers from 10 to 119 feet, best for a ready-to-hang length, or bulk spools in 500 and 1,000 feet that can be custom cut, so the string fits the project.
C9 Stringers vs. Spools
A C9 stringer is pre-sized to length with the plugs already attached, available from 10 to 119 feet and ready to hang. A C9 spool ships as continuous wire with no plugs, so you cut to the exact length your project needs. Bulk spools come in 500 and 1,000 feet, enough wire for large residential and commercial projects from a single spool.
Both are bare sockets with bulbs sold separately, so you pick the bulb and the color, and swap them later without replacing the whole string. Both are rated for indoor and outdoor use, so one string works anywhere you install it. Professional sockets feature weep holes for trouble-free performance through rain and snow.
Choose pre-sized stringers for a ready-to-hang length or bulk spools that can be custom cut so the string fits the project. A polarized fused plug on every stringer guards against electrical surges, protecting everything connected to it, and a male and female plug on every pre-sized stringer can connect one string to the next, so a single outlet can carry the whole line of light. Pre-sized stringers carry a fused plug, capping the load at 960 watts, which is more than 1,000 LED bulbs. Cut a spool between sockets and cap each end with a zip plug matched to the wire type (SPT1 or SPT2), or outdoor-rated sealant.
Add Your Own C9 Bulbs
C9 stringers and spools are bare sockets with bulbs sold separately, so you pick the bulb and the color, and swap them later without replacing the whole string. Sockets come in E17 for C9 bulbs, so you match the string to the bulb size your display calls for. Any C9 bulb with an E17 base twists into the socket, in the color, finish, and technology (LED or incandescent) you want. E17 (Intermediate) sockets accept C9 and many G-globe bulbs, so the same string can be used at Christmas and again during patio season.
Shop standard C9 bulbs and C9 LED bulbs on their own pages. Because each bulb is replaceable, a single failed bulb twists out in seconds and never makes the whole string go dark.
Choosing Your C9 Stringer: Wire Color, Spacing, and Wire Type
Wire color — available in green, white, black and brown, so the wire matches the surface it mounts on and blends in during daylight: green with greenery, white with white gutters, black with dark fascia, brown with natural wood.
Socket spacing — choose from 6 to 24 inches, so you control how full the line of light looks: tight for a dense glow up close, or wider to cover a long roofline and stretch your budget. 12-inch spacing is the most common choice for residential displays, and 6-inch gives a denser look for trees and close-up displays. C9 stringers come in 6, 12, and 18-inch spacing; C9 spools add 15 and 24-inch options.
Wire type — strings come in SPT1 or SPT2 wire, with SPT2 carrying thicker insulation for harsher weather and SPT1 handling most Christmas light displays. Heavy-duty 18-gauge commercial-grade wire reduces voltage drop so you can run longer light strings from a single power source. Built with UL Recognized Components for safety and peace of mind.
C9 Spools for Commercial Christmas Lights
For commercial Christmas lights at scale, C9 spools are the installer's default: bulk spools come in 500 and 1,000 feet, enough wire for large residential and commercial projects from a single spool, cut to length for storefronts, rooflines, and large properties. One continuous reel means fewer end-to-end connections than joining dozens of shorter strings.
For a highly customized display, add a zip plug anywhere along a C9 Christmas light string to tap power and start a new string. That lets you outline a dormer or pick up a separate design feature without running a new cord back to an outlet.
Frequently Asked Questions:
What socket spacing should I choose for C9 Christmas light strings? C9 strings are available in spacing options from 6 to 24 inches, so you control how full the line of light looks. 12-inch spacing is the most common choice for C9 rooflines and residential displays, and 6-inch gives a denser look on trees and close-up displays. C9 stringers come in 6, 12, and 18-inch spacing; C9 spools add 15 and 24-inch options.
What is the difference between SPT1 and SPT2 for C9 light strings? Strings come in SPT1 or SPT2 wire, with SPT2 carrying thicker insulation for harsher weather and SPT1 handling most Christmas light displays. Both use heavy-duty 18-gauge commercial-grade wire. When you connect sections end to end, keep the SPT rating consistent so the whole display isn't capped at the lower capacity.
What color wire should I choose for C9 Christmas lights? C9 strings are available in green, white, black and brown, so the wire matches the surface it mounts on and blends in during daylight: white on white gutters and trim, green on greenery and trees, black or brown on shingles, fascia, and natural wood.
How many C9 lights can I connect end to end? It depends on the bulbs. Each pre-sized C9 stringer carries a fused plug, capping the load at 960 watts, which is more than 1,000 LED bulbs. Wintergreen Lighting's C9 LED bulbs draw 0.8 watts or less each, far less than incandescent, so a single outlet can carry the whole line of light.
Can I cut a C9 light string or spool to length? Spools ship as continuous wire with no plugs, so you cut to the exact length your project needs: cut between sockets and cap each end with a zip plug matched to the wire type (SPT1 or SPT2) or an outdoor-rated sealant. Pre-sized stringers arrive with the plugs already attached and ready to hang, so a short display rarely needs cutting.
