1.hydra-friction swellex bolt 2.galvanized & non-galv 3.PM-12,16,20,24 4.length could be customized 5.accessories available 1.hydra-friction bolt 2.galvanized & non-galvanized3.PM-12,16,20,244.length could be customized5.accessories available high strength split steel hydra-friction swellex bolt