Also the hook . In snooker , a type of mechanical bridge that has only recently been endorsed by the WPBSA to allow its use in major tournament play. It is a normal rest with the head in line with the shaft , but the last foot or so of the shaft is curved. This allows players to position the curved end around an obstructing ball that would have otherwise left them hampered on the cue ball and in need of a spider or swan with extensions, which would have less control.