I think mine came from Barnett Performance here in Atlanta, but they should be available from Jeg's, Summit, or any performance shop.
The manufacturer is:
Flow Tech
2605 West First Street
Tempe, Arizona 85281
Phone: 602 966 1511
Part number for 2 1/2" diameter, 3 hole collectors is 10024FLT
I'm not sure about the grade of the bolts that come with them. They have a number on the head rather than the standard grade marks.
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