Lidgard Sails A0 Gennakers are primarily used for tight angle reaching. Constructed from Code Zero laminate and an A0 has a 75% mid girth to meet international sailing regulations for sail measurement. These sails can be furled and have a custom luff rope to ensure a tight luff and maximum performance. An A0 is a hugely powerful sail that can greatly improve a yachts performance reaching in light and heavy breeze.