Abstract: Disclosed are devices that include spark or particle arresting, features and muffler features. The disclosed devices may include: (a) an upstream inlet receiving exhaust gas flow; (b) a downstream outlet discharging exhaust gas flow; (c) a cylindrical body disposed between the upstream inlet and downstream outlet; and (d) a particle trap having an opening for collecting particulate matter in the exhaust gas flow, the particle trap disposed downstream of the cylindrical body on a wall of the device. The cylindrical body of the devices typically includes an annular channel permitting axial flow of gas therethrough from an upstream end of the annular channel through a downstream end of the annular channel. The downstream end of the annular channel may be configured to have openings for discharging exhaust gas flow and imparting a spiral flow to the discharged gas flow.

Abstract: Disclosed are devices that include spark or particle arresting, features and muffler features. The disclosed devices may include: (a) an upstream inlet receiving exhaust gas flow; (b) a downstream outlet discharging exhaust gas flow; (c) a cylindrical body disposed between the upstream inlet and downstream outlet; and (d) a particle trap having an opening for collecting particulate matter in the exhaust gas flow, the particle trap disposed downstream of the cylindrical body on a wall of the device. The cylindrical body of the devices typically includes an annular channel permitting axial flow of gas therethrough from an upstream end of the annular channel through a downstream end of the annular channel. The downstream end of the annular channel may be configured to have openings for discharging exhaust gas flow and imparting a spiral flow to the discharged gas flow.

Abstract: Catalyst housings and catalyst silencer housings that include various features for modularity and for servicing and securing catalysts elements, spacers and filter elements are provided.