THUNDER from TILLO International Compact and Powerful The all new THUNDER is a compact bump and jump free ride sail with medium stiffness, lots of horse power, amazing balance, extra drive and bullet proof construction. We combined the full xply body and a small Dacron mast sleeve panel to create extra power when need it, a simple format that delivers the most important thing to drive you forward .. POWER.. 4.6 M ( Luff 380 , boom 166 cm ) 5.2 M ( Luff 410 , boom 176 cm ) 5.8 M ( Luff 425 , boom 185 cm ) 6.4 M ( Luff 444 , boom 194 cm ) All around riding 4 battens, no cams Fin and Foil Full Xply construction