Designed for all wooden WaterRower machines. This row machine attachment securely holds your phone or tablet. Phone attachment comes standard with the arm. Medium and Large Tablet attachments are sold separately. WaterRower will still store upright with the arm on attached. *Not compatible with the M1 & S1. Tablet Specs: Phone Holder (Comes Standard) 2-3.5 inches iPhone X, 8 Plus, 8, 7 Plus, 7, 6s, 6, 5, 5C, 5S Samsung Galaxy S5, S4 Note 4, Note 3 Medium Tablet Holder: 6.14 – 8.66 inches 10.5 inch iPad Pro (Width = 6.8 inches) iPad (Width = 6.6 inches) iPad Mini (Height = 8 inches) Samsung Galaxy Tablet S2 8.0 (Height = 7.8 inches)