Sail batten

[1] Battens are long, thin strips of material, historically wooden but today usually fiberglass, vinyl, or carbon fiber, used to support the roach of a sail.

[2][3] Eastern lug sail, which used battens and is commonly known as "junk rig", was likely not Chinese in origin: The oldest depiction of a battened junk sail comes from the Bayon temple at Angkor Thom, Cambodia.

[6]: 21  Their rigs featured full-length battens that facilitated short-handed sail handling, including reefing.

Batten length near the head of the sail is limited by the need for the roach to pass ahead of the backstay, when tacking or jibing.

An alternative shape is a hollow tube that rotates in the batten pocket and is more compatible with roller furling the mainsail.