When i got pulled over by the boy's in blue, they gave me a yellow sticker for exhaust, pod filter, bov(non-return) and pillar mounted gauges. i went over the pits wit every thing on except bov which i returned to std, paid 30 or so dollars for permits for filter and pillar mount and have never had a problem since,when and if i get pulled over i show the police the permit and they get in their car and drive away