diff --git a/libtest.png b/libtest.png
index 85e5589..66577e1 100644
Binary files a/libtest.png and b/libtest.png differ
diff --git a/readme.md b/readme.md
index 9908a62..4e7d40e 100644
--- a/readme.md
+++ b/readme.md
@@ -2603,6 +2603,7 @@ Timing belt pulleys, both toothed and plain with internal bearings for idlers.
 ### Vitamins
 | Qty | Module call | BOM entry |
 | ---:|:--- |:---|
+|   1 | `pulley(GT2x16_pulley)` |  Pulley GT2 16 teeth |
 |   1 | `pulley(GT2x16_toothed_idler)` |  Pulley GT2 idler 16 teeth |
 |   1 | `pulley(GT2x20_toothed_idler)` |  Pulley GT2 idler 20 teeth |
 |   1 | `pulley(GT2x20_plain_idler)` |  Pulley GT2 idler smooth 12mm |
@@ -2614,6 +2615,7 @@ Timing belt pulleys, both toothed and plain with internal bearings for idlers.
 |   1 | `pulley(T2p5x16_pulley)` |  Pulley T2.5 16 teeth |
 |   1 | `pulley(T5x10_pulley)` |  Pulley T5 10 teeth |
 |   1 | `screw(M3_grub_screw, 3)` |  Screw M3 grub x  3mm |
+|   2 | `screw(M3_grub_screw, 4.5)` |  Screw M3 grub x  4.5mm |
 |   2 | `screw(M3_grub_screw, 4)` |  Screw M3 grub x  4mm |
 |   4 | `screw(M3_grub_screw, 6)` |  Screw M3 grub x  6mm |
 |   1 | `screw(M4_grub_screw, 6)` |  Screw M4 grub x  6mm |
diff --git a/tests/png/pulleys.png b/tests/png/pulleys.png
index a0d467e..5f8c5e1 100644
Binary files a/tests/png/pulleys.png and b/tests/png/pulleys.png differ
diff --git a/vitamins/pulleys.scad b/vitamins/pulleys.scad
index 00c2af8..e7f9628 100644
--- a/vitamins/pulleys.scad
+++ b/vitamins/pulleys.scad
@@ -29,9 +29,10 @@ include <belts.scad>
 //
 T5x10_pulley         = ["T5x10_pulley",         "T5",    10, 15,    T5x6,  11.6, 7.9, 7,   5, 19.3, 1.7, 3, 10.7, M3_grub_screw, 1];
 T2p5x16_pulley       = ["T2p5x16_pulley",       "T2.5",  16, 12.16, T2p5x6,   8,  16, 5.7, 5, 16.0, 1.0, 6, 3.75, M4_grub_screw, 1];
-GT2x20um_pulley      = ["GT2x20um_pulley",      "GT2UM", 20, 12.22, GT2x6,  7.5,  18, 6.5, 5, 18.0, 1.0, 6, 3.75, M3_grub_screw, 2];
-GT2x20ob_pulley      = ["GT2x20ob_pulley",      "GT2OB", 20, 12.22, GT2x6,  7.5,  16, 5.5, 5, 16.0, 1.0, 6, 3.25, M3_grub_screw, 2];
-GT2x12_pulley        = ["GT2x12_pulley",        "GT2RD", 12,  7.15, GT2x6,  6.5,  12, 5.5, 4, 12.0, 1.0, 4, 3.0,  M3_grub_screw, 2];
+GT2x20um_pulley      = ["GT2x20um_pulley",      "GT2UM", 20, 12.22, GT2x6,  7.5,  18, 6.5, 5, 18.0, 1.0, 6, 3.75, M3_grub_screw, 2]; //Ultimaker
+GT2x20ob_pulley      = ["GT2x20ob_pulley",      "GT2OB", 20, 12.22, GT2x6,  7.5,  16, 5.5, 5, 16.0, 1.0, 6, 3.25, M3_grub_screw, 2]; //Openbuilds
+GT2x16_pulley        = ["GT2x16_pulley",        "GT2",   16,  9.75, GT2x6,  7.0,  13, 5,   5, 13.0, 1.0,4.5,3.0,  M3_grub_screw, 2];
+GT2x12_pulley        = ["GT2x12_pulley",        "GT2RD", 12,  7.15, GT2x6,  6.5,  12, 5.5, 4, 12.0, 1.0, 4, 3.0,  M3_grub_screw, 2]; //Robotdigg
 GT2x20_toothed_idler = ["GT2x20_toothed_idler", "GT2",   20, 12.22, GT2x6,  6.5,  18, 0,   4, 18.0, 1.0, 0, 0,    false,         0];
 GT2x20_plain_idler   = ["GT2x20_plain_idler",   "GT2",    0, 12.0,  GT2x6,  6.5,  18, 0,   4, 18.0, 1.0, 0, 0,    false,         0];
 GT2x16_toothed_idler = ["GT2x16_toothed_idler", "GT2",   16,  9.75, GT2x6,  6.5,  14, 0,   3, 14.0, 1.0, 0, 0,    false,         0];
@@ -42,6 +43,7 @@ pulleys = [T5x10_pulley,
            T2p5x16_pulley,
            GT2x20um_pulley,
            GT2x20ob_pulley,
+           GT2x16_pulley,
            GT2x12_pulley,
            GT2x20_toothed_idler,
            GT2x20_plain_idler,