I have these 2 kicker free air subs. I was under the impression that these are meant to be run without a box but after hearing I don't think that is the
Kicker freeair 6.5C for Sale in Las Vegas, NV - OfferUp
KM Freeair Subwoofers
Kicker free air 6.5" subwoofer for Sale in Oklahoma City, OK - OfferUp
NEW OLD SCHOOL Kicker Freeair F12C SVC Competition Subwoofer,Rare,USA,NIB,NOS $199.99 - PicClick
Kicker 10" 2-ohm Marine Free Air Subwoofer with included Silver Grille. - Creative Audio
VTG Rare Old School Kicker 6x9 Free Air Subwoofers Grills Car Stereo Amplifier | eBay
KICKER Freeair F-12 Subwoofer Overview 1992 Old School - YouTube
Kicker KMF10 10-inch Marine Grade Free Air Subwoofers – Sounds Good Stereo Online
Kicker 45KMF104 10 Inch LED Marine Subwoofer in Charcoal 4 Ohm each (FreeAir) - Walmart.com