Fitness Tracker,Kirlor Blood Pressure Heart Rate Monitor Waterproof Activity Tracker (v07-Black) Fit 1 3/4",1 7/8", 2",2 1/4", 2 1/2",2 3/8" size easy installation Suitable for any angle of tower tube from Horizontal to Vertical bungee cord included (not shown in the picture) Shining polished