This is a pack of 3 Diffuser Discs for the SuperTrapp 3S Series Spark Arrestor Mufflers (sold separately). Most installations should use 1 disc per 3 horsepower for proper back pressure. This 3-pack is ideal for most 8 to 10 HP engines running above 2400 RPM without a primary muffler. Using fewer discs will further reduce noise but will also cause some power loss.
SuperTrapp mufflers are the only USDA Forest Service Approved spark arrestors that do not rely on restrictive swirl baffles or fragile screens. Sparks are funnelled into a collection chamber in the end cap, while exhaust gases exit between special diffuser discs. Even if the collection chamber filled to capacity, the small 0.023" gap between the discs still provides a back-up layer of spark protection.
We also offer a 12-Pack of 3 inch Diffuser Discs (Part No. ST-3S-6512). Use more discs on engines rated below 2400 RPM, or if the SuperTrapp will be used in conjunction with another muffler.