Thanks for the help, I had already read the rules and was wondering more about interpretation.I believe a speed puck is just a compass and speed as long as the optional software is not installed.It does indicate lifts and knocks but I believe it is not "capable of displaying stored headings and/or performing
calculations for storage of tactical information"-per 4.1.3. the problem is that it is GPS driven and that may violate 8.1.5 -Use of Loran, GPS, or similar position fixing devices. Although it seems you may be ok because it is not a " position fixing device" - it does not give position or course and therefore does it does not seem that the intent of that rule is to prohibit this device. The nice thing about the device is no wiring, one instrument at the mast, no through hull required for less or similar to the cost of a separate speed and digital compass. So my question is more along the lines of has there been a ruling? Is it legal? - I can see the argument going either way.