There are various flat, foam-cored, laminated tapered battens that work well on smaller boats (under 40 feet). They aren’t as rugged as solid glass, but are usually lighter. On larger boats, round battens work best because the round shape provides stiffness without increasing size. Plus, they’re very hard to break (for boats over 60 feet, consider carbon battens). No matter which battens you use, carry a spare on board (equal in length to the longest batten).