The Manfrotto 237HD Flexible Arm is 18mm in diameter, which is wider than the standard Flex Arm. Otherwise, it shares the same feature set: 55 cm in length with a 5/8″ hex stud to affix to the Super Clamp 035 and has a 3/8″ female thread and 1/4″ male end. This Flexarm can hold light weight fixtures or props and be easily moved and held in place without having to lock any knobs.