Automatic Vent Opener - 2 Pack

A vent opener that runs on nothing at all. A wax-filled cylinder expands as the air warms and pushes the vent open, then contracts and closes it as the temperature falls - no power, no batteries, no wiring. It starts opening between 15C and 25C, which is roughly the point at which a closed cold frame begins to cook its contents on a bright day.

• Two openers per pack
• Begins opening at 15-25C (60-77F)
• Lift capacity 6.8kg (15 lb)
• Maximum opening distance 45.7cm (18in)
• Powder-coated aluminium alloy frame
• Dual stainless steel springs
• Temperature-sensitive hydraulic wax-type cylinder actuator
• Adjustable opening angle
• Requires no electricity and no batteries
• 1-year manufacturer warranty

Fits most greenhouse roof windows, roof vents and garden cold frames; a PDF fitting manual is provided. Because it is purely mechanical there is nothing to plug in and nothing to fail electrically. Delivered free anywhere in the UK in 3-6 business days.