3595528 SWIVEL COUPLING BULK HEAD
Hiab swivel coupling, this item can be found halfway up the column/kingpost. They fit to another swivel coupling which is part number 3595510 which goes through a metal plate joining the column hoses together.
This item can be found on the following equipments;
HIAB 071A, HIAB 071AW, HIAB 095A, HIAB 095AW.