Schlage B560 B660 Supplemental Screw Replacement
By August Home | Smart Locks for Convenient, Keyless Entry | Published: 2026-10-20
Category: How-to Guides
Learn why the Schlage B560 and B660 deadbolts need longer supplemental screws for August Smart Locks, how to diagnose the problem, and the simple fix.
Quick Answer
If your August Smart Lock won't sit flush on a Schlage B560 or B660 deadbolt, the original screws are likely too short. Replace them with the longer supplemental screws designed for this retrofit—each deadbolt needs two.
Why the Original Screws Fail
The Schlage B560 and B660 are commercial-grade deadbolts with thicker mounting plates than standard residential models. The screws that ship with these deadbolts are sized for the Schlage trim, not for the added thickness of an August Smart Lock adapter. When you try to mount the August device, the screws bottom out before the lock sits flush, leaving a visible gap and an unstable fit.
This isn't a defect in your August lock or the Schlage deadbolt—it's a hardware mismatch. The fix is a simple swap to longer screws, but you need the right length and thread type to avoid damaging the deadbolt.
Trade-Offs to Consider
Using the correct supplemental screw is the cleanest solution, but you have options. Some people try to force the original screws, which can strip the threads or leave the smart lock crooked. Others use generic longer screws from a hardware store, but these may not match the thread pitch or head size, leading to a loose fit or visible overhang.
The dedicated supplemental screw is inexpensive and designed specifically for this retrofit. It's worth the small cost to avoid frustration and potential damage to your deadbolt or smart lock.
Diagnose and Fix Your Screw Problem
- Symptom: Your August Smart Lock won't sit flush against the Schlage B560 or B660 deadbolt. You may see a gap between the lock and the door, or the lock feels loose even after tightening the screws. Take a photo of the gap for reference before you start.
- Likely Cause: The original Schlage screws are too short to pass through the August mounting plate and still bite into the deadbolt. This is a known limitation of the B560 and B660 models. Confirm you have a B560 or B660 by checking the deadbolt faceplate or packaging.
- Corrective Action: Remove the August lock and the two original screws. Replace them with the supplemental screws (two per deadbolt). Reinstall the August lock, tightening each screw evenly until the lock sits flush. Do not overtighten—snug is enough to avoid stripping.
- When to Stop or Choose Another Option: If the screws still don't grip after replacement, stop and check whether your deadbolt is actually a B560 or B660. If it's a different model, the supplemental screw may not fit, and you should consult the August compatibility list or contact support. If you're unsure about the model, measure the screw length and thread pitch before ordering.
The Right Replacement Part
- Single (1) Supplemental Screw for Schlage B560 or B660: This single supplemental screw is longer than the original Schlage B560 and B660 screws, which are too short for August Smart Lock installation. The extra length lets the screw reach the deadbolt's threads while accounting for the August adapter, giving you a secure, flush mount.
Single (1) Supplemental Screw for Schlage B560 or B660
