RAM Mount Long Double Socket Arm w/2.5" Round Base [RAM-B-103U-C] Marine Plumbing & Ventilation but the 5206-N has a

but the 5206-N has a nylon ferrule

The included back plate is interchangeable with various size support cups

These stainless steel backing plates are a perfect match for Rupp Rod Holder installations

Bucket Seat

RAM Mount Long Double Socket Arm w/2.5" Round Base [RAM-B-103U-C] Marine Plumbing & Ventilation but the 5206-N has aRAM 1" Diameter Ball Long Double Socket Arm with 2. 5" Round Base that contains the AMPs Hole Pattern Overall Length: 6. 62" The RAM B 103U C consists of a 2. 5" round base and LONG double socket arm that will accept 1" ball bases. The round base contains pre drilled holes, including the universal AMPS hole pattern. Designed into the mount is a 1" diameter patented rubber ball and socket system with adjustment points at both ends of the socket arm;