The Schlage 09-158 is the OEM L Series anti-ligature conversion kit in 630 Satin Stainless Steel finish, specifically for converting the L460, L480, and L9460 cylinder-by-thumbturn deadbolt functions to the SDB1 ligature-resistant deadbolt design. It ships with two components: one ligature-resistant blocking ring and one ligature-resistant thumbturn assembly. This kit is for 1-3/4" thick doors with sectional trim only. It does not apply to rose trim installations or doors outside the 1-3/4" standard thickness.

The conversion is a field installation. The existing standard thumbturn assembly is removed and replaced with the SDB1 ligature-resistant thumbturn from this kit. The blocking ring fills the gap between the thumbturn and the door trim face to eliminate any recess, ledge, or edge that could anchor a cord, sheet, or other flexible material.

What the Schlage L Series Anti-Ligature Kit Addresses

A ligature point is any protrusion, recess, or anchor location on a room surface where a flexible material - a cord, belt, shoelace, torn fabric - could be tied or looped in a way that creates strangulation risk. Standard thumbturn assemblies on mortise deadbolts have exposed rotating bodies with graspable edges. Even a small lip or wing on the thumbturn creates a ligature anchor point.

The SDB1 ligature-resistant thumbturn replaces that graspable profile with a design that has sloped, recessed surfaces and no horizontal projections. There's nowhere for a ligature to catch. The blocking ring supplements this by closing the gap at the trim face - that small annular gap around a standard thumbturn is itself a potential anchor point for thin material. The blocking ring eliminates it.

Per Allegion's ligature-resistant product documentation, Schlage HSLR solutions carry the "Paperclip Protection" designation as determined by NYS-OMH (New York State Office of Mental Health) testing, enabling use in low-, medium-, and high-risk behavioral health areas.

Schlage Deadbolt Anti-Ligature Conversion: L460, L480, L9460 Functions

The three functions this kit converts are all cylinder-by-thumbturn deadbolt configurations:

L460 is the Cylinder x Thumbturn Small Case Mortise Lock. The deadbolt is actuated by key from outside or thumbturn from inside. Closing the door throws the deadbolt automatically and the deadbolt cannot be held retracted.

L9460 is the Cylinder x Thumbturn Sectional Trim Mortise Lock - functionally identical to the L460 but in the L9000 Series (sectional trim, full-size case rather than small case).

L480 is a related deadbolt function in the L Series family.

All three share the same thumbturn format that the 09-158 kit replaces with the SDB1 ligature-resistant assembly.

Schlage L Series Anti-Ligature Kit Family

The 09-158 is one of several L Series conversion kits in the Schlage ligature-resistant catalog. The correct kit depends on the installed function:

09-157 converts L462, L464, L9462, and L9464 (double cylinder deadbolt functions) to ligature resistance. 

09-158 (this product) converts L460, L480, and L9460 (single cylinder with thumbturn deadbolt functions). 

09-159 converts L9040 and L9440 to ligature resistance.

For lever and knob anti-ligature conversions - converting L Series entrance and storeroom functions - the 09-138, 09-139, 09-155, and 09-156 kits apply to different function groups. All conversion kits share the same 1-3/4" door, sectional trim restriction.

If the installation requires the highest ligature-resistance level - the HSLR (High Security Ligature Resistant) full chassis and trim replacement rather than a conversion kit - Schlage's HSLR L Series product line provides that solution as a complete factory-built assembly.

SecurityParts stocks OEM Schlage L Series ligature-resistant conversion kits and mortise lock parts.