diff --git a/main.scad b/main.scad
index f77b39b..3d88a6a 100644
--- a/main.scad
+++ b/main.scad
@@ -3,6 +3,7 @@ include <BOSL/constants.scad>
 use <BOSL/transforms.scad>
 use <BOSL/shapes.scad>
 use <BOSL/masks.scad>
+use <BOSL/sliders.scad>
 
 // DEBUG:
 //validation = 1;
@@ -12,6 +13,8 @@ use <BOSL/masks.scad>
 MODEL_HARNESS_LEFT=1;
 MODEL_HARNESS_RIGHT=2;
 MODEL_HARNESS_TOP=3;
+MODEL_HARNESS_SLIDER_FRONT=4;
+MODEL_HARNESS_SLIDER_BACK=5;
 export=0; // [0:5]
 function is_not_export() = is_undef(export) || export == 0;
 function is_export() = !is_not_export();
@@ -20,14 +23,6 @@ function is_model(m) = is_not_export() || export == m;
 
 function get_phone_size() = [160, 76.7, 10];
 
-shell_wall=3;
-shell_rim_wall=3;
-rim_edge_thickness=1.2;
-rim_edge_tolerance=0.4;
-expose_back_camera=false;
-screwmount_screw=3;
-harness_divider=[30, 0, 1.3];
-
 module phone() {
     s=get_phone_size();
     color("gray")
@@ -43,10 +38,23 @@ module arm() {
 module phone_harness() {
     ops=get_phone_size();
     ps=[ops.x+0.2, ops.y+0.2, ops.z+0.2];
+    shell_wall=3;
+    shell_rim_wall=3;
+    rim_edge_thickness=1.2;
+    rim_edge_tolerance=0.4;
+    expose_back_camera=false;
+    screwmount_screw=3;
+    harness_divider=[16, 0, 1.3];
+    harness_size=[ps.x+shell_wall*2, ps.y+shell_wall*2, ps.z+shell_wall*2];
+    rim_size=[harness_size.x+2*shell_rim_wall, harness_size.y+2*shell_rim_wall, 6];
+    
     w=shell_wall;
     f=2;
     rf=5;
-    hs=[ps.x+w*2, ps.y+w*2, ps.z+w*2];
+    hs=harness_size;
+    backplane_rim_size=[30, ps.y*0.95, shell_wall/2];
+    
+    // ==== SHELL ====
     
     module shell() {
         $fn = $preview ? 6 : 30;
@@ -60,7 +68,7 @@ module phone_harness() {
     module shell_rim() {
         $fn = $preview ? 6 : 30;
         w=shell_rim_wall;
-        s=[hs.x+2*w, hs.y+2*w, 6];
+        s=rim_size;
         intersection() {
             difference() {
                 cuboid(s, fillet=rf, edges=EDGES_Z_ALL);
@@ -68,6 +76,9 @@ module phone_harness() {
             }
             cuboid(s, fillet=1);
         }
+        rail_extension=10;
+        fwd(hs.y/2) xrot(90) harness_rail(slider_len_front+rail_extension);
+        back(hs.y/2) xrot(-90) harness_rail(slider_len_back+rail_extension);
     }
     module shell_rim_edge(thickness, groove, tolerance=rim_edge_tolerance) {
         $fn = $preview ? 6 : 30;
@@ -103,7 +114,38 @@ module phone_harness() {
             up(hs.z-1) cylinder(d=screwmount_screw+1.5, h=5);
         }
     }
+    module shell_backplane(groove) {
+        down(hs.z/2 - shell_wall/6) up(backplane_rim_size.z/2) right(harness_divider.x) scale(groove ? 1.01 : 1) cuboid(backplane_rim_size, fillet=5, edges=EDGES_Z_LF);
+    }
     
+    // ==== SHELL SLIDER AND RAIL ====
+    
+    rail_angle=36;
+    rail_wall=1;
+    slider_slop=0.1;
+    slider_len_back=hs.x*0.3;
+    slider_len_front=hs.x*0.3;
+    module harness_slider(l) {
+        base=2;
+        ss=[l, shell_rim_wall, rim_size.z+rail_wall*2];
+        up(ss.y + base) xrot(180) slider(l=ss.x, w=ss.z, h=ss.y, base=base, chamfer=0.9, wall=2, ang=rail_angle, slop=slider_slop, orient=ORIENT_X, align=V_UP);
+    }
+    module harness_rail(l) {
+        sw=2;
+        ss=[l, shell_rim_wall, rim_size.z+rail_wall*2];
+        rail(l=ss.x, w=ss.z, h=ss.y, chamfer=0.5, ang=rail_angle, orient=ORIENT_X, align=V_UP);
+    }
+    
+    // ==== SHELL CUTOUTS ====
+    module shell_cutouts() {
+        top_cutout();
+        bottom_cutout();
+        left_cutout();
+        right_cutout();
+        front_cutout();
+        shell_screwmounts_holes();
+    }
+    // -- TOP --
     module screen_cutout() {
         s=[138, 69, 100];
         up(s.z/2) cuboid(s, fillet=3, edges=EDGES_Z_ALL);
@@ -130,6 +172,7 @@ module phone_harness() {
         leds_cutout();
     }
     
+    // -- BOTTOM --
     module back_camera_cutout() {
         s=[13, 25, expose_back_camera ? 100 : 11];
         right(ps.x/2 - 7.5) fwd(ps.y/2 - 23) down(s.z/2 - ps.z/3) cuboid(s, fillet=6, edges=EDGES_Z_ALL);
@@ -153,6 +196,7 @@ module phone_harness() {
         bottom_speaker_cutout();
     }
     
+    // -- RIGHT --
     module headphones_cutout() {
         $fn = $preview ? 10 : 30;
         d=8.8;
@@ -164,6 +208,7 @@ module phone_harness() {
         headphones_cutout();
     }
     
+    // -- LEFT --
     module usbc_cutout() {
         s=[100, 20, 6];
         left(ps.x/2) down(2) cuboid(s, fillet=1);
@@ -172,6 +217,7 @@ module phone_harness() {
         usbc_cutout();
     }
     
+    // -- FRONT --
     module buttons_cutout() {
         s=[42, 100, 5];
         fwd(ps.y/2) right(ps.x/2 - 44.5) cuboid(s, fillet=1);
@@ -180,14 +226,7 @@ module phone_harness() {
         buttons_cutout();
     }
     
-    module shell_cutouts() {
-        top_cutout();
-        bottom_cutout();
-        left_cutout();
-        right_cutout();
-        front_cutout();
-        shell_screwmounts_holes();
-    }
+    // ==== MODEL ====
     
     divider=harness_divider;
     module model_harness_left() {
@@ -200,6 +239,7 @@ module phone_harness() {
                 shell();
                 shell_rim_edge(rim_edge_thickness, groove=true, tolerance=rim_edge_tolerance);
                 shell_cutouts();
+                shell_backplane(groove=true);
             }
         }
     }
@@ -215,6 +255,7 @@ module phone_harness() {
                 shell_cutouts();
             }
         }
+        shell_backplane(groove=false);
     }
     module model_harness_top() {
         intersection() {
@@ -229,10 +270,21 @@ module phone_harness() {
             shell_cutouts();
         }
     }
+    module model_harness_slider_front() {
+        difference() {
+            fwd(hs.y/2) xrot(90) harness_slider(slider_len_front);
+            front_cutout();
+        }
+    }
+    module model_harness_slider_back() {
+        back(hs.y/2) xrot(-90) harness_slider(slider_len_back);
+    }
     
     if (is_model(MODEL_HARNESS_LEFT)) model_harness_left();
     if (is_model(MODEL_HARNESS_RIGHT)) model_harness_right();    
     if (is_model(MODEL_HARNESS_TOP)) model_harness_top();
+    if (is_model(MODEL_HARNESS_SLIDER_FRONT)) model_harness_slider_front();
+    if (is_model(MODEL_HARNESS_SLIDER_BACK)) model_harness_slider_back();
 }
 
 module model() {