diff --git a/HPGLWrap.py b/HPGLWrap.py
index f0da2e9..f09dab4 100755
--- a/HPGLWrap.py
+++ b/HPGLWrap.py
@@ -36,8 +36,8 @@ def pre_content(filename, power=50, speed=50, rate=2500):
     # Use same value for all 16 pens
     # doesn't seem to affect vector settings
     outString += write_pen_values([speed * 10] * 16, 'V') # Velocity, 1000=100%
-    outString += write_pen_values([power * 10] * 16, 'V') # Power, 1000=100%
-    outString += write_pen_values([rate] * 16, 'V') # PPI
+    outString += write_pen_values([power * 10] * 16, 'P') # Power, 1000=100%
+    outString += write_pen_values([rate] * 16, 'I') # PPI
     outString += "%1B"
 
     return outString