PUMP’s SIZE TABLE Please use our formula to calculate the size of Bathmate Pump that is right for you. Current Erect Length Current Erect Width Room for growth Hydromax 3 / HydroXtreme 3 for a penis that less than 3 in. 3 in 1.0 in 1.5 in Hydromax 5 For a penis that is 3-5 in. 3-5 in 1 3/4 in 1.5 in Hydro 7 / Hydromax 7 / HydroExtreme 7 Same features as Hydromax 5 / 9 Provide faster gains for guys whose penis in no longer than 5-7 in. New Swivel Bellows feature & new Super Flow Latch Valve system 5-7 in 2.0 in 1.5 in Hydromax 7 Wide Boy / HydroXtreme 7 Wide Boy 5-7 in 2 1/4 in 1.5 in Hydromax 9 / HydroExtreme 9 Same features as Hydromax 5 / 7 Provide faster gains for guys whose penis in no longer than 7-9 in. New Swivel Bellows feature & new Super Flow Latch Valve system 7-9 in 2 1/4 in 1.5 in HydroExtreme 11 for a penis that is 9-11 in. 9-11 in 2 1/2 in 1.5 in