diff --git a/tests/hygrometer.scad b/tests/hygrometer.scad
new file mode 100644
index 0000000..b9802d9
--- /dev/null
+++ b/tests/hygrometer.scad
@@ -0,0 +1,22 @@
+//
+// NopSCADlib Copyright Chris Palmer 2018
+// nop.head@gmail.com
+// hydraraptor.blogspot.com
+//
+// This file is part of NopSCADlib.
+//
+// NopSCADlib is free software: you can redistribute it and/or modify it under the terms of the
+// GNU General Public License as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// NopSCADlib is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with NopSCADlib.
+// If not, see <https://www.gnu.org/licenses/>.
+//
+use <../vitamins/hygrometer.scad>
+
+if($preview)
+    hygrometer();
diff --git a/tests/png/hygrometer.png b/tests/png/hygrometer.png
new file mode 100644
index 0000000..57186a5
Binary files /dev/null and b/tests/png/hygrometer.png differ
diff --git a/vitamins/hygrometer.scad b/vitamins/hygrometer.scad
new file mode 100644
index 0000000..e29baf4
--- /dev/null
+++ b/vitamins/hygrometer.scad
@@ -0,0 +1,86 @@
+//
+// NopSCADlib Copyright Chris Palmer 2018
+// nop.head@gmail.com
+// hydraraptor.blogspot.com
+//
+// This file is part of NopSCADlib.
+//
+// NopSCADlib is free software: you can redistribute it and/or modify it under the terms of the
+// GNU General Public License as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// NopSCADlib is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with NopSCADlib.
+// If not, see <https://www.gnu.org/licenses/>.
+//
+
+//
+//! Mini LCD Celsius Digital Thermometer Hygrometer Temperature Humidity Meter Gauge on eBay
+//
+include <../core.scad>
+
+od = 40.9;
+h = 14;
+flange_d = 45.5;
+flange_t = 1.5;
+flange_d2 = 32;
+flange_t2 = 2;
+apperture_d = 24.7;
+hygrometer_hole_r = 21.3;
+slot_w = 5.5;
+
+module hygrometer_hole(h = 0) { //! Drill the hole for a hygrometer
+    round(cnc_bit_r) {
+        intersection() {
+            drill(hygrometer_hole_r, h);
+
+            rotate(30)
+                square([slot_w + 2 * cnc_bit_r, 100], center = true);
+        }
+        drill((od + 0.2) / 2, h);
+    }
+}
+
+function hygrometer_or() = flange_d / 2; //! The outside radius of a hygrometer
+
+module hygrometer() { //! Draw a hygrometer
+    vitamin("hygrometer(): Mini LCD Digital Thermometer / Hygrometer");
+
+    explode(40) {
+        color(grey30)
+            rotate_extrude()
+                polygon([
+                    [0, 0],
+                    [apperture_d / 2, 0],
+                    [apperture_d / 2, flange_t],
+                    [flange_d2 / 2,   flange_t2],
+                    [flange_d / 2,    flange_t],
+                    [flange_d / 2,    0],
+                    [od / 2,          0],
+                    [od / 2,          -h],
+                    [0,               -h]
+                ]);
+
+        color("#94A7AB")
+            cylinder(d = apperture_d, h = eps);
+
+        color("black")
+            linear_extrude(height = 0.2, center = true) {
+                translate([0, 3])
+                    text("20_4", font = "7 segment", valign = "bottom", halign = "center", size = apperture_d / 6);
+
+                translate([7, 3])
+                    text("C", font = "7 segment", valign = "bottom", halign = "center", size = apperture_d / 8);
+
+                translate([-1.9, 0.5])
+                    text("50", font = "7 segment", valign = "top", halign = "center", size = apperture_d / 2.7);
+
+                translate([0, -apperture_d / 6])
+                    text("          %", font = "Arial", valign = "center", halign = "center", size = apperture_d / 6);
+            }
+
+    }
+}