Ram Mount (RAM-B-238U) 2.43 x 1.31-Inch Diamond Ball Base with 1-Inch Ball (Black) 1" diameter rubber ball connected at right angles to a 2.43" x 1.31" diamond base The base has two holes 1.912" from center to center Will connect to a large variety of RAM Mount and third party cradles Powder Coated Marine Grade Aluminum Powder Coated Marine Grade Aluminum 1" Rubber Ball "B" Size Base has two holes 1.912" from center, matches the standard AMPS hole pattern and will connect to a large variety of RAM Mount & third party cradles The RAM-B-238U consists of a 1" diameter rubber ball connected at right angles to a 2.43" x 1.31" diamond base Lifetime warranty