diff --git a/snap_on_templates.py b/snap_on_templates.py
index 2ae2e9a..de69af0 100644
--- a/snap_on_templates.py
+++ b/snap_on_templates.py
@@ -32,7 +32,7 @@ notch_height = 1.5
 notch_depth = 0.5
 
 
-def lishi_template(spec: BittingSpecification, name: str, depth: float):
+def lishi_template(spec: BittingSpecification, name: str, depth: float, profile: cq.Sketch):
     key_guide_width = lishi_width/2 + side_thickness + spec.TFC - spec.BCC/2
 
     result = (
@@ -66,8 +66,7 @@ def lishi_template(spec: BittingSpecification, name: str, depth: float):
         .tag("key_guide")
         .edges("not <Y").fillet(corner_radius)
         .faces(">X", tag="key_guide").vertices("<Z and <Y").workplane(centerOption="CenterOfMass").center(0, bottom_thickness + lishi_cutter_offset - depth)
-        # ideally, the key profile would be passed in as an argument
-        .rect(spec.key_thickness + extra_key_thickness, depth, centered=False).cutThruAll()
+        .placeSketch(profile).cutThruAll()
         .union(result)  # this seems like a fairly bad way to do this, but it does work
     )
 
@@ -86,5 +85,18 @@ def lishi_template(spec: BittingSpecification, name: str, depth: float):
 
 spec = key_bittings.national_disc_tumbler
 for name, depth in spec.depths.items():
-    result = lishi_template(spec, name, depth)
+    profile = (
+        cq.Sketch()
+        .push([((spec.key_thickness + extra_key_thickness)/2, depth/2)])
+        .rect(spec.key_thickness + extra_key_thickness, depth)
+
+        # notch to hold key straight
+        .push([(spec.key_thickness + extra_key_thickness - 0.5, 0.5 + 0.5)])
+        .rect(1, 1, mode="s")
+
+        # fillet inner corners
+        .reset().vertices("not(>X or <X)") .fillet(0.3)
+    )
+
+    result = lishi_template(spec, name, depth, profile)
     exporters.export(result, f'national_disc_tumbler_{name}.stl')