These are not commerial grade quality
Muffler / Exhaust assembly to fit the 11hp through to 16hp Honda clone engines. Also fits the genuine GX340 and GX390 engines.
Two mounting centers are approximately 50mm apart
Exhaust bore is approximately 25mm in diameter
This muffler assembly is not suitable for a plate compactor or anything similar where the engine is being thumped. You can get braced mufflers which are the best for these appications