We have become aware that some new North sails have a small vinyl window to allow viewing of the jib tell tales. This window does not comply with H Class rules. These sails therefore cannot be used in the H Class Championship unless the window is covered with opaque tape.
Here is the Rule:
All sails shall be made of woven fabric. Mainsails and jibs shall be made of Dacron® or similar woven polyester material of minimum weight of four ounces per sailmakers’ yard (28.5″ x 36″), and the material shall not be coated, such as yarn tempered material. However, the mainsail may have one anti-collision window made of flexible transparent Vinyl or other non-woven polymer material. The window may be no greater than 288 Sq. in. and may have seams pass through it.