Ullman Viper 640 Mainsail

Ullman Viper 640 Mainsail us.viper640.Mainsail
$1,470.00/ Qty Add to Cart
Add to Wish List
Add to Favorites

Item #: us.viper640.Mainsail

Why a Dacron Mainsail?

Other sailmakers build their Viper 640 mainsails out of laminate material, but the Ullman Sails Viper 640 mainsail uses woven Dacron, which has proven to be fastest and easiest to use across the wind range.

Automatic shift

Because we've arranged the crosscut panel orientation to place the cloth's thread line slightly off the load path in the critical upper-batten area of the mainsail, the leech automatically opens the right amount in gusts and as the wind builds -- an important adjustment that mainsails made of laminate material do not make.      

Class Model

The Ullman mainsail features a radial head and clew sections of Contender Dacron to handle loads, and the remainder of the sail is crosscut of 4.52 oz Contender Dacron for maximum adjust ability across the wind range. 

Goes faster, longer.

Finally, the Class model mainsail not only goes through the wind range better and easier (letting  you concentrate on racing instead of sail tweaking), the woven Dacron material holds its shape longer than laminate mainsails.


  • Loose Foot
  • Class insignia, draft stripes
  •  RBS tapered racing battens with top 3 full battens (RBS adjusters)
  •  sail numbers, telltales, cunningham
  • adjustable leech and foot cords
  • floating tack
  •  foot vision window 
  • roll bag

    Product TypeSails

    Customer Reviews

    Recently Viewed Items

    eCommerce Shopping Cart Powered by Logicblock