Passive tightened after automatic rotary. This is designed for central driving reeling and unreeling equipment, especially for flange single end or both ends.
Specifications : 
● 3" Outer diameter : ψ75.5 mm
● Expanded diameter : ψ79 mm/max
● Inside diameter of paper tube : ψ76.2 ± 0.2 mm
Remarks :
Other sizes of outer diameter such as 1" to 12" are available on request.