Stock 77

Sealing locknut - 1/2 in trade size - steel with yellow PVC seal - LK.5S

SKU: MC-LK.5S

1/2 in steel sealing locknut with a yellow PVC sealing ring for securing threaded conduit to a box or enclosure in wet or damp locations. Commonly used where a raintight seal is needed at the knockout; verify conduit type, trade size, and listing requirements before installation.

What this product is for

This sealing locknut is used to secure threaded conduit or threaded fittings to an enclosure while adding a sealing surface at the knockout. It is intended for applications where moisture resistance is required.

Use for

Use for rigid conduit or IMC terminations into boxes, cabinets, and enclosures where a sealing locknut is specified. It is commonly used in wet or damp location terminations with a compatible threaded fitting.

Avoid for

Avoid using this as a substitute for a standard locknut where no sealing function is required, or where the connected fitting and enclosure are not intended for wet-location use. Do not assume suitability for EMT unless the fitting assembly is specifically designed and listed for that application.

Best for

Best for electricians needing a simple sealing locknut for 1/2 in trade size threaded conduit entries, especially where a PVC sealing ring helps reduce water ingress at the enclosure wall.

Installed in

Typically installed in panels, junction boxes, pull boxes, meter bases, and outdoor or industrial enclosures. 1/2 in trade size corresponds to approximately 16 mm nominal trade size.

Why this product exists

A standard locknut secures the fitting mechanically, while a sealing locknut adds a gasketed sealing surface. This helps electricians build a more weather-resistant connection at the enclosure entry point.

Compared with similar products

Compared with a standard steel locknut, a sealing locknut adds a PVC sealing element for wet-location style terminations. Compared with a separate sealing ring and standard locknut, this style can simplify material selection when the assembly is compatible with the fitting and enclosure.

Specifications

Product type: Sealing locknut
Trade size: 1/2 in (approximately 16 mm)
Material: Steel
Seal colour: Yellow
Seal material: PVC
Application: Secure threaded conduit or fittings to boxes and enclosures where a sealing locknut is required
Typical use: Wet or damp location terminations, subject to the complete fitting assembly and listing
Standards reference seen on comparable products: UL 514B

Typical guidance only: sealing locknuts are commonly selected when a raintight or weather-resistant entry is needed at the enclosure wall. Actual performance depends on the fitting used, enclosure condition, torque, and local electrical code.

- SKU
  MC-LK.5S
- Manufacturer Part #
  LK.5S
Application
Secure threaded conduit or fittings to boxes and enclosures where a sealing
Material
Steel
Trade Size
1/2 in (approximately 16 mm)
Seal Material
PVC
Brands
White Label
Stock in Elmira
55
Stock in Flesherton
22

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