Cycling Trousers

that folded and assembled into a bag they came with.I took the bike and I was wondering if anyone knew what they are called and where I might get one.I have looked on many websites, but in vain .
Grateful for any help.

http://www.montane.co.uk/
Go to the products and watch the "fast and lean range. The pants and jackets go into a stuff sack the size of a tennis ball and are incredibly lightweight, waterproof, windproof and breathable. Ideal for cyclists.

look-up "raincoats" in stores such as REI, LLBean, and EMS ..

http://www.rei.com/
http://www.llbean.com/
http://www.ems.com/

You can get them at most bike shops.