The hull lines and exterior styling of the Slup, which was ordered by experienced sailors, were designed by the Bremerhaven-based design office Judel/Vrolijk, while the interior was designed by Wetzels Brown Partners from Amsterdam. Hall Spars supplied the carbon rig, North Sails laminated the 3Di wardrobe. The first Contest 85 CS, built as a GRP sandwich, was designed to sail around the world.