Dryade blocks are made in a wide variety of sizes accepting sheaves of diameters from 30 to 160 mm in standard series. The technical and marine shells, in noble wood of various species, are worked in coffee bean form and curved on the inside of the cheeks so that the rigging can be passed easily while keeping chaffing to a minimum. Sharp angles are eliminated in order to lend softness to the forms and to guarantee long varnish life. The finished shells are protected by multiple coats of standard varnish.