If you’re a K&N fan or you use your their filters in your truck of off-road vehicle, check out this awesome K&N Air Filter Keychain. This pint-sized version of their classic cone-shaped filter would be the perfect addition to you set of keys. Known as the world’s leading manufacturer of washable performance air filters, K&N Engineering sells over 5,000 products in over 30 different countries. The Air Filter Keychain is available to order online directly from K&N’s website. The keychain sells for $9.99 and you might want to pick up a second one for a buddy as it would make a great gift for a fellow truck nut.