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Southwire 500 ft. 18/3 Solid Copper Thermostat Wire

Southwire 500 ft. 18/3 Solid Copper Thermostat Wire

Made in America

Support American manufacturers + independent hardware retailers in one purchase.

Solid copper conductors and direct-burial durability make this 18/3 wire a dependable choice for thermostat and HVAC control runs.
Southwire MPN 64168845
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 $0.39
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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About Product Overview

This is Southwire's 18/3 thermostat wire, a 500-foot roll built for running low-voltage control lines between thermostats, HVAC equipment, doorbells, and similar systems. The solid copper conductors carry signal reliably, and the thermoplastic insulation is rated for direct burial and UL listed for indoor use. Flame-retardant construction and sunlight/UV resistance give it some flexibility for a range of installation spots, though it's not rated for wet locations.

  • 18 AWG, 3-conductor solid copper wire
  • 500-foot roll, sold by the foot
  • Voltage rating: 150V; temperature rating: -20° to 60°C
  • UL Listed, flame retardant, direct burial rated
  • Made in the USA

The Details Specifications

Brand Southwire
UPC 032886438523
Case Pack Quantity 2 per case
Retail Unit Quantity 500
Dimensions (L × W × H) 7 × 7 × 6
Weight 10 lbs
Country of Origin USA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab
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