Mortise lock LOB 155 (without cylinder) — model 155, backset 35 mm

Mortise lock LOB 155 (without cylinder) — model 155 with a 35 mm backset is a mechanical mortise locking unit designed for installation in prepared wooden or metal doors. The lock provides a spring latch for standard door closing and a separately operated deadbolt depending on the door preparation and chosen handle or key cylinder. Supplied without a cylinder, this mortise lock is intended to be combined with a compatible profile cylinder and strike plate to achieve secure locking for interior or exterior doors in residential or light commercial settings.

Advantages

This mortise lock features a compact mechanism with a 35 mm backset that fits common door preparations and allows for straightforward replacement or installation. The design separates latch and deadbolt functions, enabling flexible operation via handle and cylinder. Constructed for mechanical reliability, the unit is compatible with standard door furniture and strike plates, and its configuration without a cylinder allows customers to choose the cylinder type and security level appropriate for their application.

Suitable for (tasks / use cases)

• Replacement of existing mortise locks in residential interior or exterior doors
• Installation in new doors requiring a 35 mm backset mortise lock
• Doors where custom cylinder selection is required for matched security or master-key systems
• Light commercial premises with moderate security demands

Key specifications

• Lock type: mortise lock body without cylinder
• Model: 155
• Backset: 35 mm
• Functions: spring latch and deadbolt operation (depending on door preparation and fitted cylinder/handle)
• Compatible with profile cylinders and standard strike plates
• Suitable for wooden or metal doors with appropriate mortise preparation

How to use

Prepare the door edge and faceplate mortise according to the lock's dimensions and the door manufacturer's recommendations. Insert the mortise lock body into the prepared cavity and secure it with screws through the faceplate. Fit a compatible profile cylinder into the cylinder hole and fasten it to the lock body following the cylinder supplier's instructions. Install the strike plate on the door frame aligned with the latch and deadbolt positions. Test the handle operation, latch retraction, and cylinder-operated deadbolt to ensure smooth engagement and correct alignment before regular use.

Usage recommendations

For reliable operation, choose a quality profile cylinder matched to the intended security level and ensure the strike plate is reinforced and correctly aligned. Periodically check screws and alignment, lubricate moving parts with a dry or recommended lock lubricant, and follow local building codes for exterior door installations.