boom lock

Question

I have a windsurfer brand Duralite 12 foot freestyle board. It has a boom that
uses a rope to secure it to the mast.
what do you call  the part
that locks on the boom and eliminates tying it on?
And do you know where I can get one............tnanks

Answer
The mechanism that attaches the boom to the mast is called an inhaul. The particular part that you need may not be available since many of the old boards have components that were proprietary.  It is nearly impossible to get parts for old boards for this reason.  There is only one place in the US that may have a few parts for older boards.

http://www.the-house.com/windsurfing.html

Keep in mind that the older the board, the more difficult they will be to sail.  The newer boards made in the last 5 to 8 years are vastly superior to the old ones.  The older boards usually begin to absorb water and become quite heavy and difficult to sail.  I am not trying to sell you a new board but you will not believe the difference in sailing a newer board. They are much easier to sail and much more fun.  I know because I still have my old Wayler that I learned on 30 years ago and while I can still sail it, it is like sitting on a log compared to the board I bought 6 years ago.