Mast Slug Drilling block (Fits Tack Tick compass mount.)

Instruments are typically held to sailboat masts using slugs in the sail track. The slug gives the equipment something to screw to that can be adjusted up and down. A slug is usually a piece of round aluminum bar-stock with threaded holes drilled crosswise in it.

How does one align a drill bit to drill these holes? Using a Mast Slug Drilling block. This one will align 3 holes in a 3/8" x 2+" piece of aluminum bar-stock. Perfect for mounting a tack tick compass mount. Assuming you've lost the