Replacement Hydraulic damper for the MK7 Hydraulicheck autovent.
If you have a Mk 7 autovent that is no longer functioning, this is NOT the part you require to get it working again. The part which operates the unit is the Mk 7 standard power tube . These can be found at https://www.baylissautovents.co.uk/product/mk-7-standard-power-tube/