Motorcycle Repair: Suzuki VL1500LC Intruder air filter switch, k n air filter, original style

Question
I want to go the the K&N air filter.  Do I order just one or do I need two to replace the orginal air filters on my 1999 Intruder?

Answer
Dale,

-if you want the original style just order one
that fits, the K&N SU-1598.

-I would avoid single filters because of the
big air sucking noise you will hear if you
remove the original air filter box.

http://www.knfilters.com/search/product.aspx?Prod=SU-1598