Chinook 2-bolt Mechanical base Upper

Chinook 2-Bolt Upper with Mechanical Joint

This mast base is designed to work with the Chinook 2-bolt base plate.  The pin on the bottom of the base fits into the Chinook 2 bolt plate, but it will not fit into older style windsurfing boards with an adjustable mast track (even though it looks similar).  The mechanical joint makes it easier to attach the sail to your board, especially if you have a wider windsurfing board that is difficult to hold on its side in the water.  That means this base works great if you have a Chinook 2-bolt base plate on your larger, wider beginner windsurfing board.