diff --git a/doc/links.md b/doc/links.md
index 97913b8..1d41bb2 100644
--- a/doc/links.md
+++ b/doc/links.md
@@ -1,2 +1,3 @@
 https://arduinodiy.wordpress.com/2017/01/02/reviewing-the-wemos-battery-shield/
 https://arduinodiy.wordpress.com/2016/12/25/monitoring-lipo-battery-voltage-with-wemos-d1-minibattery-shield-and-thingspeak/
+https://www.thingiverse.com/thing:3015533
diff --git a/firmware/config.h b/firmware/config.h
index 39287e2..49be99b 100644
--- a/firmware/config.h
+++ b/firmware/config.h
@@ -1,6 +1,7 @@
 
-#define DEBUG 1
+//#define DEBUG 1
 
+#define BATTERY_POWERED 1
 #define POWERSAVING 1
 
 #define SENSOR_TEMPERATURE    0
diff --git a/firmware/firmware.ino b/firmware/firmware.ino
index d46f73c..88db53e 100644
--- a/firmware/firmware.ino
+++ b/firmware/firmware.ino
@@ -62,6 +62,8 @@ void setup() {
 
   digitalWrite(STATUS_LED_PIN, HIGH);
 
+  lowBatCheck(getBatteryVoltage());
+
   // Establish WiFi connection
   String wifiName = "oko-weather-" + String(ESP.getChipId());
 
@@ -111,7 +113,7 @@ void setup() {
 
   digitalWrite(STATUS_LED_PIN, LOW);
 
-  lowBatCheck();
+  lowBatCheck(currentSensorData[SENSOR_BAT_VOLTAGE]);
 
   WiFi.mode(WIFI_OFF);
   WiFi.forceSleepBegin();
@@ -126,9 +128,9 @@ void setup() {
 
 //*************************************************************************//
 
-void lowBatCheck()
+void lowBatCheck(float v)
 {
-  if (currentSensorData[SENSOR_BAT_VOLTAGE] <= BAT_LOW_VOLTAGE)
+  if (v <= BAT_LOW_VOLTAGE)
   {
 #ifdef DEBUG
     Serial.println("Low battery, going into deep sleep.");
@@ -140,8 +142,6 @@ void lowBatCheck()
 
 void loop() {
 
-  lowBatCheck();
-
 #ifdef POWERSAVING
   delay(50);
   return;
diff --git a/hardware/ht-dn50_stopfen.scad b/hardware/ht-dn50_stopfen.scad
index a877828..89a1c76 100644
--- a/hardware/ht-dn50_stopfen.scad
+++ b/hardware/ht-dn50_stopfen.scad
@@ -1,22 +1,24 @@
-
-
-union() {
-	difference() {
-		cylinder(h=30, r=25, $fn=300);
-		translate([0, 0, -5])
-            cylinder(h=40, r=23, $fn=300);
-	}
-    difference() {
-        union() {
-            translate([0, 0, 30])
-                cylinder(h=3, r=30, $fn=300);
-            color("green")
-                translate([-22, -12, 31])
-                    cube([44, 24, 5]);
-        }
-        color("red")
-            translate([-20, -10, 25])
-                cube([40, 20, 15]);
-    }
-}
-
+
+radius=25;
+height=30;
+
+union() {
+	difference() {
+		cylinder(h=height, r=radius, $fn=300);
+		translate([0, 0, -5])
+            cylinder(h=height+10, r=radius-2, $fn=300);
+	}
+    difference() {
+        union() {
+            translate([0, 0, height])
+                cylinder(h=3, r=radius+5, $fn=300);
+            color("green")
+                translate([-22, -12, 31])
+                    cube([44, 24, 5]);
+        }
+        color("red")
+            translate([-20, -10, 25])
+                cube([40, 20, 15]);
+    }
+}
+