The TMF-1 is a wide-based trailer fin for use as a 5th fin option, adding just a little more control to your favourite quad. Made in Huntington Beach, the Thermotech product line does not have the traditional plastic feel of a composite fin. Instead, they have a consistent flex that creates drive and release through turns. Template Category - Wide-base Trailer. Construction | Thermotech. Size | X-Small Trailer. Height 1.76 base 3.76 Area 4.85 Foil SYMM.