National Mfg N178-822 Silver Knob Latch with Key

Product Description

The NATIONAL MFG/SPECTRUM BRANDS HHI N178-822 is a silver knob latch with key designed for wood or metal screen and storm doors. It features a dual locking design with an exterior key lock that operates independently from the interior locking mechanism, providing enhanced security at the entry point. The zinc die cast spring-loaded strike plate is included, along with mounting screws finished to match the hardware. This unit is packaged in a quantity of 3 and weighs 2.75 pounds. Licensed locksmiths, carpenters, and general contractors typically install this type of door hardware during new construction or replacement service calls.

This latch is suited for residential screen and storm door applications on both wood and metal door frames. It accommodates hole spacing of 1-1/2 inches, 1-3/4 inches, or 3 inches, making it compatible with a wide range of standard door prep configurations. For wood doors, it fits door thicknesses from 5/8 inches to 1-3/8 inches. The separate interior locking mechanism adds a secondary layer of access control without requiring the exterior key, making it practical for back entries, porch enclosures, and secondary egress points where keyed security is preferred.

Key Features

• Dual locking design: exterior key lock operates separately from the interior locking mechanism
• Fits hole spacing of 1-1/2 inches, 1-3/4 inches, or 3 inches
• Compatible with wood doors 5/8 inches to 1-3/8 inches thick
• Designed for wood or metal screen and storm doors
• Spring-loaded strike plate manufactured from zinc die cast included
• Mounting screws included and finished to match product hardware
• Uses Y11 key blank N223-990 1308K for key replacement

Compatibility

Designed for wood or metal screen and storm doors with hole spacing of 1-1/2 inches, 1-3/4 inches, or 3 inches. Fits wood doors from 5/8 inches to 1-3/8 inches thick.

Installation Notes

Install by a qualified carpenter, locksmith, or experienced DIYer following the door manufacturer guidelines. Power tools are not required, but a hand drill may be needed to adjust or clean out existing bore holes before fitting. Ensure the door is fully closed and stable before aligning the strike plate. Do not over-tighten mounting screws, as this may distort the latch mechanism alignment on thinner door panels.