quality:correction, structural:expansion, linguistic:paraphrasing
Dartboard

According to the Darts Regulation Authority, a regulation board is 451 mm (17.8 in) in diameter and is divided into 20 radial sections. Each section is separated with metal wire or a thin band of sheet metal.

Quality dartboards are still made of sisal fibres from Eastern Africa, Brazil, and China; less expensive boards are sometimes made of cork or coiled paper.