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Southwire 250 ft. 18/4 Solid Copper Thermostat Wire

Southwire 250 ft. 18/4 Solid Copper Thermostat Wire

Made in America

Support American manufacturers + independent hardware retailers in one purchase.

A 250-foot supply of solid copper 18/4 wire keeps your thermostat and HVAC control wiring jobs covered without a mid-run splice.
Southwire MPN 553040407
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 $0.59
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.

  • Authorized dealer network · Full manufacturer warranty & support
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  • The brands set these standards · Be wary of sellers who don't follow them
Why isn't this online? The whole story →

About Product Overview

This 250-foot roll of Southwire 18/4 thermostat wire gives you enough solid copper conductor to handle most HVAC control wiring jobs without running short. The four 18-gauge conductors carry low-voltage signals between thermostats, furnaces, and air handlers, and the PVC/thermoplastic jacket is flame retardant and UL Listed for indoor installations.

Rated 150 volts with a temperature range of -20 to 60, it's built for the conditions inside walls and mechanical rooms. Made in the USA.

  • 18/4 solid copper conductors
  • 250 ft. length
  • 150V rating, -20 to 60 temperature range
  • UL Listed, flame retardant, indoor use

The Details Specifications

Brand Southwire
UPC 029892354084
Case Pack Quantity 4 per case
Retail Unit Quantity 250
Dimensions (L × W × H) 4 × 7 × 7
Weight 7 lbs
Country of Origin USA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab
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