Chinook Base One-Bolt Twist-On Mechanical Mast Base (US Cup) now from $57.95. 2009 MSRP is $62.95 
NEW YEAR LIQUIDATION LOW PRICES TO START THE YEAR! EXTRA DISCOUNT ON PHONE ORDERS UNTIL FRI. JAN.9. FREE SHIPPING* on ORDERS OVER $99 (Restrictions apply - see TERMS. Closeout Boards Excluded). NO SALES TAX (U.S. Only). All Prices in USD.
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The mechanical base offers the most rigid contact between the rig and board with no shock absorption. The tendon and flex-joint will over time wear and possibly break but the mechanical parts will not. It is preferred by schools for its durability. Rotation is the smoothest and it allows you to attach the rig to board without turning the board on its side because you are not working against the flexible joints. The base can be loosened for quick mast track adjustments even in the water. 1-bolt design offers a little more fore/aft adjustment in the mast track than the 2-bolt design.