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Triple Spring Bayliss MK 7 Vent Opener

This Bayliss MK7 Triple Spring is an extremely reliable automatic vent opener.
This particular unit is designed to be fitted to top hinged, side windows or exposed roof vents, the three springs fitted are designed to hold the windows / vents firmly in place in windy conditions, and with the extra springs, to exert a greater closing force.


£42.50
SKU VEMK7TS
For side windows up to approx.36" x 24" (92cm x 61cm).

Bolts on to aluminium greenhouses (fixings supplied) - for wooden greenhouses it is attached by wood screws (not supplied).

Fits neatly close to the glass the opener does not protrude into the greenhouse.

Satin anodised aluminium unit approx. 11˝" (29cm) long which exerts a load of 13lbs (6kg) i.e. it will lift a vent weighing up to 26lbs (12kg).

Can be set to start opening the vent at any temperature between 12-25ş Centigrade/55-75ş Fahrenheit, giving a maximum window opening of 12" (30cm).

Operated by a stainless steel cylinder containing a mineral wax which expands with heat, this pushes a piston causing the vent to open. As the temperature falls the wax contracts and a strong stainless steel spring closes the opener.

Supplied complete with comprehensive installation instructions.

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Bayliss guarantee their openers for 2 years but if anything should go wrong after that replacement cylinders are readily available and easy to fit.


Click Here to see full and comprehensive fitting instructions for this Bayliss Vent Opener.


To Learn More About How Automatic Vent Openers Work Click Here