i have been using a set of aura bass shakers and had them in my 93 f150 super cab ,anothe truck and now in my 98 f150 super cab. they offer two sets a 100 watt system and a 50 watt system. what they are is a set of 5 inch subs incased in a casting with a thin layer of cork on the bottom they come with a 100 watt digital bass amp a external level control the 2 bass shakers 24 feet of monster speaker wire connectors and rca cable (alternitive high level pigtail to spice into wires if no rca available included) all for 100-180 depending on the 100 or 50 system. what this system does is increases the bass boost with out the high costs of a sub and boxes and taking up space.they wont give you huge bass like a sub as to where people twenty feet away will hear it but this is what it it does do. by mounting the subs to the floor (subs are less than three inces high (2.25 high and 6.25 diam) they almost flush mounted after cutting carpet. you cut carpet in a u or H pattern and once installed carpet will hide speaker. run speaker wire to amp which has two crossover settings 80/120 and is small in size with an adjustable gain. but this also has a external level control which you can mount under the dash or on the center consel. using this you can adjust the gain from the drivers seat it will raise or lower the intensity of bass from where it is set on the amp. as i said everybody and there brother wont hear it from twenty feet away but inside the cab is unbelivable by mounting it to the floor (sheetmetal) bass is transmitted threw everything (even your butt will get a masage. you do hear the bass also but now that you upgraded the stock speakers and still have no thump or big boom this will give it back. my 88 f-250 i had 12 inch mtx boxes behind the seat and when i bought the supercab i hated it no place for speakers and still have room for the kids. i was hesitant but for a hundred bucks i bought the 50 watt sett up and was impressed when i sold the truck i wanted to keepthem but the new owner paid me extra to leave them in so i was able buy the 100 watt set up and it was a huge improvement and anyone that rides in it was equily impressed they will fit under the front seats or the back because of there size.info on them is aura systems inc 2335 alaska ave. el segundo ca 90245 ph 310-643-5300 fax 310-536-9159 i neverlooked for them on the internet