The RAM Mount Universal Marine Electronic Mount - C Size consists of a short double socket arm, 2.5" diameter round base, and 6.25" x 2" rectangle base. The round base includes a 1.5" C size rubber ball and contains pre-drilled holes, including the universal AMPS hole pattern. The rectangle base also includes a 1.5" C size rubber ball and contains a variety of pre-drilled holes that are compatible with several marine electronic devices, including fishfinders and chartplotters. 

Short RAM-111U-B:

Overall Height: 5.225". SOCKET TO SOCKET LENGTH 2.5"

Medium RAM-111U:

Overall Height: 7.35". SOCKET TO SOCKET LENGTH 4.66"

Long RAM-111U-D:

Overall Height: 10.85". SOCKET TO SOCKET LENGTH 8"