3 joint and each joint can turn 360 degree nd can be detachable.
air adjusting valve of Joint:  designed to match round tube for manual adjustment.  Through an external valve knob could adjust valve to control the air flow
﹡Suction: PC dome hood at the bottom of the exhaust arm, can be detachable and washed easily.
﹡Installation: According the space to adjust the way to install.  There are ceiling mounting, wall brackets and bench mounting and ceiling mounting is most popular one.
﹡Ceiling column material is plated with zinc and stainless steel. Painted with epoxy after.  Make the whole piece fume exhaust stronger and resistant acid.

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