True Ames TA Single Tab Tri-Fin SetThe True Ames Single Tab Tri Fin Set design inspiration and key elements include taking everything they've learned about making glass on tri fins over the past 40+ years and rolling all of that into this design. The TA tri is another template from our in house collection and is our version of the tried and true thruster design that was first popularized in the early 80's and has continually evolved since. Fin Size Detail Size Height Base Area Small 4.