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Southwire 250 ft. 18/5 Solid Copper Thermostat Wire

Southwire 250 ft. 18/5 Solid Copper Thermostat Wire

Made in America

Support American manufacturers + independent hardware retailers in one purchase.

Direct burial rated and UL listed, this 250-ft spool handles indoor and outdoor thermostat runs without extra scraps left over.
Southwire MPN 64169644
Sold Locally Only

This product isn’t sold on our website — see your local hardware store.

Typical Store Price i
Typical store price: low $0.99, average $0.49
In-Store Exclusive

This one's worth the trip to the store.

Brands like Weber, Milwaukee, Yeti, and DeWalt restrict where their products can be sold online — and for good reason. In-store buyers get authentic products, full manufacturer warranty, and access to pricing that simply isn't allowed to be advertised on the web.

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Why isn't this online? The whole story →

About Product Overview

Southwire's 18/5 thermostat wire covers the wiring jobs most HVAC installs call for, with five solid copper conductors under a nylon jacket for durability. It's rated for direct burial and holds up to outdoor sun exposure, so it works whether you're running a line indoors to a new thermostat or outside to a heat pump or condenser unit. UL listed and flame retardant, this 250-foot spool gives you enough length for multiple runs without leftover scraps sitting around.

  • 18-gauge, 5-conductor solid copper wire
  • Nylon jacket, thermoplastic insulation
  • Direct burial and UV/sunlight resistant
  • 150V rating, -20°F to 60°F temperature range
  • UL Listed and flame retardant
  • 250 ft. spool, made in the USA

The Details Specifications

Brand Southwire
UPC 032886855337
Case Pack Quantity 2 per case
Retail Unit Quantity 250
Dimensions (L × W × H) 7 × 7 × 4
Weight 8 lbs
Country of Origin USA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab
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