What is the difference between an H16J and an H16M? What does the J and M stand for and how do I know which one I have? Mine is a 1985 model. Thanks.
AE
I can only imagine that this is a reference to the Main Sail or Jib Sail.
H16M (Main?)
H16J (Jib?)
The main sail is the larger (much larger) sail.
Where did you see the reference?
I think you're right. The reference is in the 2006-2007 Accessories and Parts catalog in a "Battens" table (page 18). I didn't realize that the jib had battens. See what a cat newbie I am? 
Get ready for more dumb questions in the future. Thanks for the help.
AE
If you have a jib furling system your jib may not have battens.
We all started somewhere. I wish I had known about this site when I first got my boat. Learning the hard way takes a lot longer.