Don't use brushes or compressed air and you won't damaged the filter media. I've never found a need to do either of those things to clean my K&N's over the many years I have been using them.

2000 SVT Turbo 295hp/269ftlb@12psi #1 for Bendix Brakes Kits! Knuckles rebuilt w/new bearings $55 AUSSIE ENDLINKS $70 Gutted pre-cats $80/set A lack of planning on your part does not constitute an emergency on mine!