well give up the info mang!
My bad. I thought I put a link in there.
Just gotta be carefull when fixing brass fittings to it…
http://www.joewoodworker.com/catalog/product_info.php?cPath=60_36&products_id=58
The switch that is being used is the Air Logic model V-5100.
It can be found for about 5-10 bucks cheaper if you have an air logic distributor close to you. There are a couple online places that sell it in addition to joe woodworker.
bigchevman, thank you for the manufacturer’s name! 
http://www.air-logic.com/catalogs.cfm?Action=ShowTopCategory&TopCategoryID=2