lol I had my car for 4 years and didnt know incabin's existed in our cars til a few months ago. and.... :GASP!: it looked like some one **** all over it... after changing it I have a lot more air that flows threw the vents.. it's kinda nice. lol nissan recommends to change the about every 15k... i dunno how often we're supposed to change ours but it's prolly around the same