BDTSR.

Partially right on the Quadra 40. The early models used 2 rings while the later model uses 1 ring. Also I believe on Quadra the first two numbers of the serial number is the size. B&B Specialties is the Quadra dealer and has ign. parts. Recomend using their points eliminator. [link]http://bennettbuilt.com[/link]

Scott