250' Thermostat Wire, UL 18/5

The Southwire 553050407 Thermostat Cable provides reliable signal transmission for low-voltage temperature control and HVAC applications.

Engineered for general-purpose use, the Southwire 553050407 Thermostat Cable features five solid bare copper conductors insulated with durable PVC for excellent electrical performance and flexibility. Rated for 300 volts, this 18 AWG cable is ideal for thermostat wiring, heating and air conditioning controls, and alarm or communication circuits in both residential and commercial environments.

• Model number 553050407 identifies this Southwire 18 AWG, 5-conductor Thermostat Cable designed for low-voltage control systems.
• Rated for 300 volts and suitable for general-purpose indoor applications.
• Features solid bare copper conductors for dependable conductivity and low resistance.
• Supplied in a 250-foot length for convenient installation in residential or commercial projects.

Technical Data & Specifications

• Manufacturer: Southwire Company, LLC
• Model Number: 553050407
• Product Type: Thermostat Cable (General Purpose)
• Voltage Rating: 300 V
• Number of Conductors: 5
• Conductor Size: 18 AWG
• Conductor Type: Solid Bare Copper
• Insulation Material: Polyvinyl Chloride (PVC)
• Jacket Material: PVC (color-coded)
• Cable Length: 250 feet (76.2 meters)
• Temperature Rating: Typically -20°C to +60°C (-4°F to +140°F)
• Application: Low-voltage control and communication wiring
• Usage: Thermostat control, heating and air conditioning systems, doorbells, and alarm wiring
• Installation Type: Suitable for concealed, exposed, or conduit installations (dry locations only)
• Shielding: Unshielded
• Compliance: UL Listed, Type CL2 (Class 2 Power-Limited Circuit Cable)
• Flame Rating: UL 13 compliant for general-purpose use
• Marking: Sequential footage marking for easier installation measurement
• Packaging: Supplied on a reel or coil, depending on distributor
• Country of Origin: USA (or as marked on product packaging)
• Warranty: Southwire Limited Warranty against manufacturing defects

Features & Benefits

• Five 18 AWG solid bare copper conductors ensure reliable low-voltage signal transmission.
• Rated for 300 volts — ideal for thermostat and control circuits.
• Durable PVC insulation resists abrasion, chemicals, and moisture in indoor environments.
• Color-coded conductors simplify identification and installation.
• Flexible construction allows easy routing and handling during setup.
• Suitable for HVAC systems, alarms, intercoms, and temperature control wiring.
• Meets UL and NEC requirements for Class 2 power-limited circuits.
• Available in 250-foot length for professional and residential installations.