The ST G51 uses the exact same muffler as the ST 46 and V60. There are plenty of tongue and lightweight tube mufflers out there available from Randy Smith @ Aero Products, Tom LAy @ T&L, RSM, Brodak, Tom Dixon, Stuka Stunt Works, Big Art Adimisin, Windy Urtnowski, and most C/L Hobby Shops. It has been a common muffler for over 20 years.
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