its the exact same as the regular 6.
i used to work at checker auto and we could order them. a guy came in with a speed 6 and i checked the part number and its the same as the normal 6. plus they are 15 bucks ordered at checker rather than 30 at the dealer. just FYI.
Unfortunately, that is not accurate.
I've been through the ringer on this issue, visited almost every parts store (Pep Boys/Autozone/Advanced Auto/NAPA/Consumer Auto Parts (CAP, Massachusetts only), and, in a nutshell, no one carries the right part.
Autozone claims their own brand, called STP Kleener, has a part # for this, and that part number is CAF1864P, but since there is no store that carries it, and apparently, they can't special order it, because it doesn't officially exist in inventory. Go figure.
Further, you will find indications (while Googling) that the following:
Mazda: GK3J-61-14V
Purolator: C35643
Are both valid for the Speed6. THAT IS INCORRECT.
The purolator part # above is for the Mazda 6i, and the length dimensions are off. No you can't cut it shorter with an xacto, because you'd be cutting against the pleats. The Mazda part # above... not sure what that is, but I suspect it's incorrect.
As someone above mentioned, the correct MAZDA part # is GJ6B-61-P11, and the retail cost is $50.71. Interesting fact though, is that the dealership cost is only $27.70. So, if you end up paying full retail, like I did, you are getting absolutely raped.
OK, last but not least. I visited Advanced Auto, and they claim to have the right part through 2 manufacturers:
Beck/Arnley 042-2129 $30
IMC 093-32008-501 $11.99
I was not willing to special order these, as I just don't believe that these are correct. But, if someone wants to give it a go, it would be nice to get this settled once and for all.
I personally just bought the Mazda part, and called it "end game"
Hope some of this is helpful to you guys.