Home Vision World Multimedia On board with EF: #4 - Metron 81 SL and Metron TFW 23 Jul 2021 On board with EF: #4 - Metron 81 SL and Metron TFW Metron TFW is a result of several months of work for Vision engineers in order to provide the fastest TT wheel ever to the pro riders of EF Pro Cycling with benefit in terms of rigidity and lightweight. The aero package is completed by Metron 81 SL Disc, the Vision’s Aero Triathlon and Time Trial focused wheelset.