Next Generation Load Sensing for Standing Rigging on Sports and Day boats. The smarttune 5/16" (the smallest in the smarttune range) is designed specifically for sports and day boats. In minutes it easily swaps in for your existing turnscrew (forestay/backstay/shrouds/diagonals), and moments later can be displaying live load data on your phone wirelessly, or (with the addition of a Cyclops Marine Gateway) on most on-board electronics systems. SmartTune has been precision designed for low weight, low windage. Factory calibrated and accurate to +/- 2% of maximum working load. Durable and waterproof to beyond IP67. Powered by CR2032 batteries. Pair with smartfittings app for logging and analysis. Recommended wireless range of up to 15m while sailing (connect to on-board displays via Gateway for longer range). Our Part # CYC-SMRTUNE516 | Cyclops Marine Part # TS516B