diff --git a/src/platform.scad b/src/platform.scad
index cb368cc..b82c083 100644
--- a/src/platform.scad
+++ b/src/platform.scad
@@ -1,6 +1,6 @@
 include <export.scad>
 //export=MODEL_PLATFORM_HARNESS;
-//export=MODEL_PLATFORM_STRAP;
+export=MODEL_PLATFORM_STRAP;
 
 // dependency: https://github.com/revarbat/BOSL
 include <BOSL/constants.scad>
@@ -53,12 +53,14 @@ module lock_arm() {
     translate([joiner_size.x/2, joiner_size.y/2, -joiner_size.z/2 + size.z/2]) cube(joiner_size, center=true);
 }
 module lock_mechanism_button(groove=false) {
-    button_size=groove
-        ?[10,5]
-        :[7,4.5];
-    size=[button_size.x, get_platform_wall()*7, button_size.y];
-    translate([get_platform_lock_pin_size().x*1.5, -get_platform_size().y/2+size.y*1.3, -get_platform_size().z/2])
-    cube(size, center=true);
+    button_size=get_platform_lock_button_profile(groove);
+    size=get_platform_lock_button_size(groove);
+    translate(get_platform_lock_button_pos())
+    left(groove?1:0)
+    difference() {
+        cube(size, center=true);
+        up(size.z/2 + (groove?0.5:0)) back(3) cube(size, center=true);
+    }
 }
 module lock_buttons_cutout() {
     module cutout_side(groove) {
@@ -108,6 +110,12 @@ module platform(base) {
     top_size=get_platform_top_size();
     top=!base;
     
+    module base_platform_cutout_for_top() {
+        base_top_diff=[base_size.x-top_size.x, base_size.y-top_size.y];
+        guiding=0.4;
+        translate(get_platform_top_pos()) down(top_size.z/2) prismoid(size1=[top_size.x,top_size.y], size2=[top_size.x+base_top_diff.x*guiding,top_size.y+base_top_diff.y*guiding], h=top_size.z);
+            lock_buttons_cutout();
+    }
     module base_platform() {
         module base_platform_core() {
             braced_thinning_wall(h=size.y, l=size.x, thick=size.z, wall=0, strut=wall, orient=ORIENT_X_90);
@@ -115,8 +123,7 @@ module platform(base) {
         
         difference() {
             base_platform_core();
-            translate(get_platform_top_pos()) down(top_size.z/2) prismoid(size1=[top_size.x,top_size.y], size2=[base_size.x-2,base_size.y-2], h=top_size.z);
-            lock_buttons_cutout();
+            base_platform_cutout_for_top();
         }
     }
     module top_platform() {
@@ -126,8 +133,11 @@ module platform(base) {
         
     module strap_connectors() {
         //down(size.z/2)
-        foreach_platform_strap_connector() {
-            link_connector_pin();
+        difference() {
+            foreach_platform_strap_connector() {
+                link_connector_pin();
+            }
+            base_platform_cutout_for_top();
         }
     }
     
@@ -151,6 +161,11 @@ module model_platform_strap() {
     platform(base=true);
 }
 
+// Validation:
+/*intersection() {
+    model_platform_harness();
+    model_platform_strap();
+}*/
 // Export:
 difference() {
     union() {
diff --git a/src/specs_platform.scad b/src/specs_platform.scad
index ea734de..b1205e8 100644
--- a/src/specs_platform.scad
+++ b/src/specs_platform.scad
@@ -19,5 +19,17 @@ function get_platform_strap_connector_offset() = [
     ];
 
 function get_platform_lock_pin_size() = [20, 4, 3];
-function get_platform_lock_arm_size() = [65, 2, 3];
-function get_platform_lock_pin_pos() = [-20, -get_platform_top_size().y/2 + get_platform_wall()*4 + 1, get_platform_top_size().z/2];
+function get_platform_lock_arm_size() = [46, 2, 3];
+function get_platform_lock_pin_pos() = [-get_platform_lock_pin_size().x/2, -get_platform_top_size().y/2 + get_platform_wall()*4 + 1, get_platform_top_size().z/2];
+function get_platform_lock_button_profile(groove) = groove ? [10, 5] : [7, 4.5];
+function get_platform_lock_button_size(groove) = [
+    get_platform_lock_button_profile(groove).x,
+    get_platform_size().y * 0.25 + get_platform_lock_pin_size().y + 2,
+    get_platform_lock_button_profile(groove).y
+    ];
+function get_platform_lock_button_pos() = [
+    get_platform_lock_pin_size().x/2 + 5,
+    -get_platform_lock_button_size(false).y/2,
+    -get_platform_size().z/2
+    ];
+