These are manufacturred in BSP series(1/2", 3/4", 1", 1 1/4"), UNF series(1 1/16", 1 3/16", 1 5/16", 1 7/16") and metric series(m20 to m52) and sleeves from 1/2"BSP to 1 1/4" BSP.
Material is SAE1018, the after forging is superior in quality, with better surface finish, annealed structure and increased toughness free from surgace cracks.