MS1861 Series MS® Bottom Rail Deadbolt

MS1861 Bottom Rail Deadbolt provides maximum security with MS deadbolt locking mechanism. It utilizes hardened steel bolts for the limited space of ultra-narrow stile doors.


The MS1861 lies horizontally in the bottom rail of ultra-narrow stile doors which have insufficient vertical space for a lock, or tempered glass doors which have no stile at all. The hardened steel cylindrical bolts allow simple drilled strike holes of a relatively small size to minimize the nuisance and danger presented by some threshold strikes in collecting debris or snagging on high-heeled shoes. MS1861-02 locks either single-leaf or pairs of doors. Not recommended for wood doors.



360° turn of key or thumbturn projects or retracts bolt(s). Key can be removed only when bolts are in a positively locked or unlocked position. Lock accepts any standard 1" [25.4 mm] length, 1-5/32" [29.4 mm] diameter mortise cylinder with MS® cam such as the 4036 Mortise Cylinder or thumbturn such as the 4066 Thumbturn, available separately. Lock accepts cylinder from either or both sides.



Cylinder Backset: Minimum backset is approximately 2-1/4" [57.2 mm] for the MS1861- 01 configuration with vertical bolt only. The MS1861-02 configuration with both vertical and horizontal bolts requires placement of cylinder centerline 5-3/4" [146.1 mm] from nose of door. Both have cylinder center 1-7/8" [47.6 mm] above bottom edge of door.

Case: Measures 1" x 6" x 1-13/16" [25.4 mm x 152.4 mm x 46.0 mm]. Steel with corrosion-resistant plating.

Bolt: 3/8" [9.5 mm] diameter. Stainless steel vertical threshold bolt has 13/16" [20.6mm] throw. Hardened steel horizontal bolt has 1-1/8" [28.6 mm] throw.

Strike: In metal installation, 7/16" [11.1 mm] drilled holes in threshold are required. For MS1861-02 configuration with both vertical and horizontal bolts, drilled holes are also required in jamb or opposite door.

Standard Package: Individually boxed with mounting screws. Cylinder and/or thumbturn available separately. If required, tube spacers are available separately.

Shipping weight: MS1861-01: 1-3/4 lbs [0.79 kg], MS1861-02: 2 lbs [0.91 kg]



• Vertical bolt only (-01)
• Vertical and horizontal bolts (-02) 


Related Products: When purchasing this product, please consider the following related products, available separately:

Accessories Cylinders

4014 Conversion Kit available separately for multi-point locking applications. MS1861 may be ordered with vertical and horizontal bolts (Bolt Operation option 2).

Tube spacers (26-00090XX)

Standard 1" length, 1-5/32" diameter mortise cylinder with MS® cam such as 4036 Mortise Cylinder, 4066Thumbturn