Pneumatic Time Delay Switch 6A, FTS Single Pole Change-over Contact Adjustable 10sec to 10mins approx

This is the Flexicon FTS40 Pneumatic 6 Amp Time Lag Switch 10Sec-10Min (approx), a single-pole change-over contact switch. 

It is designed for incandescent and fluorescent lighting circuits, and it can be used for either new installations or for replacement of existing single gang units. The timer can be used on its own, or with other units in a 2-wire (no neutral) lighting circuit.

• This pneumatic time delay switch is easy to use and to fit; it is a pneumatic switch that turns off lighting automatically with an adjustable time delay. 
• No more lights left on: you can save money!
• Ideal for staircases, hallways, corridors, and storage cupboards
• You can reduce wasted energy and work to environmental targets
• It has a single gang design, suiting both new installations or replacing existing wall switches
• It is simple to install, and it has a snap action switch mechanism
• Switch current rating at 240V AC: for incandescent / GLS 6A, for fluorescent 3A, and for compact fluorescent 3A peak (6 fittings max).
• Adjustable time delay: 10 seconds to 10 minutes (approx)
• It has been designed for 20mm or 25mm deep standard BS single gang mounting boxes; deeper boxes should be used where space is required for additional cables. 
• Pressing the plunger button to operate the switch will "make" or "break" the change-over contacts. The plunger will return to its start position during the time delay, returning the contacts to their original position using the snap action of the switch. 
• The face plate is semi-translucent and a flash can occasionally be seen when the contacts "make" or "break". 
• The Time Delay is adjustable (10 seconds to 10 minutes approx) by turning the brass timing screw in the centre of the rear plate (clockwise will increase the delay).