diff --git a/sbc_case_builder_accessories.cfg b/sbc_case_builder_accessories.cfg
index 86c36fd..6a4097e 100644
--- a/sbc_case_builder_accessories.cfg
+++ b/sbc_case_builder_accessories.cfg
@@ -866,16 +866,17 @@ accessory_data = [
              "sub","vent",-3.5,30,4,"bottom",[0,0,90],["case",false,false,false],2,6,4,1,17,"vertical",1,                               // vent opening
              "sub","vent",111.5,30,4,"bottom",[0,0,90],["case",true,false,false],2,6,4,1,17,"vertical",1,                               // vent opening
              "sub","fan",99,10,48,"top",[0,0,90],["sbc-case_z",true,true,true],90,0,6,2,0,"",0,                                         // fan opening
-             "sub","rectangle",-5,76,33.5,"top",[0,0,0],["sbc",true,true,true],6,8,15,0,0,"vertical",[.25,.25,.25,.25],                   // usb opening
-             "sub","rectangle",-5,85.5,33.5,"top",[0,0,0],["sbc",true,true,true],6,8,15,0,0,"vertical",[.25,.25,.25,.25],                   // usb opening
-             "sub","rectangle",-5,95,33.5,"top",[0,0,0],["sbc",true,true,true],6,8,15,0,0,"vertical",[.25,.25,.25,.25],                   // usb opening
-             "sub","round",-5,87,51.5,"top",[0,90,0],["sbc",true,true,true],3,0,6,0,0,"",0,                                      // port extender hole
+             "sub","rectangle",-5,76,33.5,"top",[0,0,0],["sbc",false,true,true],6,8,15,0,0,"vertical",[.25,.25,.25,.25],                   // usb opening
+             "sub","rectangle",-5,85.5,33.5,"top",[0,0,0],["sbc",false,true,true],6,8,15,0,0,"vertical",[.25,.25,.25,.25],                   // usb opening
+             "sub","rectangle",-5,95,33.5,"top",[0,0,0],["sbc",false,true,true],6,8,15,0,0,"vertical",[.25,.25,.25,.25],                   // usb opening
+             "sub","round",-5,87,51.5,"top",[0,90,0],["sbc",false,true,true],3,0,6,0,0,"",0,                                      // port extender hole
              "add1","access_port",10,30,-0.01,"bottom",[0,0,0],["sbc",true,true,false],100,80,2,0,0,"landscape",0,                      // access port
              "add2","button",12.34,106.43,53,"top",[0,0,0],["sbc-case_z",true,true,true],10,0,53,0,0,"recess",0,                        // button
              "add2","button",23.77,106.43,53,"top",[0,0,0],["sbc-case_z",true,true,true],10,0,53,0,0,"recess",0,                        // button
              "model","button_top",12.34,106.43,53,"top",[0,0,0],["sbc-case_z",true,true,true],10,0,58,0,0,"recess",0,                   // button top
              "model","button_top",23.77,106.43,53,"top",[0,0,0],["sbc-case_z",true,true,true],10,0,58,0,0,"recess",0,                   // button top
-             "model","h3_port_extender",1,0,-0.01,"bottom",[0,0,0],["sbc",true,true,false],0,0,0,0,0,"landscape",0,                      // access port cover
+//             "model","h3_port_extender",-1,70,18.5,"bottom",[0,0,0],["sbc",true,true,false],0,0,0,0,0,"landscape",0,                      // access port cover
+             "model","h3_port_extender",6,70,18.5,"bottom",[0,0,0],["sbc",true,true,false],0,0,0,0,0,"landscape",0,                      // access port cover
              "model","access_cover",10,30,-0.01,"bottom",[0,0,0],["sbc",true,true,false],100,80,2,0,0,"landscape",0,                    // access port cover
              "platter","button_top",-20,0,0,"top",[0,0,0],["case",false,false,false],10,0,58,0,0,"recess",0,                            // button top
              "platter","button_top",-30,0,0,"top",[0,0,0],["case",false,false,false],10,0,58,0,0,"recess",0,                            // button top
diff --git a/sbc_case_builder_library.scad b/sbc_case_builder_library.scad
index 1ab19bf..edb8f71 100644
--- a/sbc_case_builder_library.scad
+++ b/sbc_case_builder_library.scad
@@ -3449,5 +3449,23 @@ module vent(width,length,height,gap,rows,columns,orientation) {
 // odroid-h3 gpio port extender
 module h3_port_extender() {
 
-    translate([7,258.5,103]) rotate([90,0,270]) import("stl/h3_port_extender.stl");
+//    translate([7,258.5,103]) rotate([90,0,270]) import("stl/h3_port_extender.stl");
+    translate([1.6,188.5,84]) rotate([90,0,270]) import("stl/h3_port_extender.stl");
+
+    // gpio 24 pin front position
+    translate([-3,15.75,0.25]) rotate([90,180,180]) import("stl/header_f_2x12_90.stl");
+
+
+    // gpio 24 pin rear position
+//    translate([4.55,18.25,0.25]) rotate([90,180,0]) import("stl/header_f_2x12_90.stl");
+    
+    // serial header rear position
+//    color("yellow") translate([6.5,4,29.25]) rotate([180,90,0]) import("stl/header_2x5_90.stl");
+  
+    // serial enclosed header rear position
+//    color("yellow")translate([9,-.5,12.75]) rotate([0,270,90]) import("stl/header_encl_2x5_90.stl");
+    
+    // power button
+    translate([-2.5,0,29.5]) rotate([270,0,90]) import("stl/header_2x2_90.stl");
+
 }
diff --git a/stl/h3_port_extender.stl b/stl/h3_port_extender.stl
new file mode 100644
index 0000000..0d7069e
Binary files /dev/null and b/stl/h3_port_extender.stl differ
diff --git a/stl/header_2x2_90.stl b/stl/header_2x2_90.stl
new file mode 100644
index 0000000..ed34be9
Binary files /dev/null and b/stl/header_2x2_90.stl differ
diff --git a/stl/header_2x5_90.stl b/stl/header_2x5_90.stl
new file mode 100644
index 0000000..cca7a7e
Binary files /dev/null and b/stl/header_2x5_90.stl differ
diff --git a/stl/header_encl_2x5_90.stl b/stl/header_encl_2x5_90.stl
new file mode 100644
index 0000000..d3f2de6
Binary files /dev/null and b/stl/header_encl_2x5_90.stl differ
diff --git a/stl/header_f_2x12_90.stl b/stl/header_f_2x12_90.stl
new file mode 100644
index 0000000..dec63ec
Binary files /dev/null and b/stl/header_f_2x12_90.stl differ