This flexible arm with molded acetal copolymer links and ball-and-socket joints accepts the F18317-1000 Electrode Holder (sold separately) at one end, with a stainless steel pin at the other for attachment to the weighted base.Four octagonal wells centered along the base edges for affixing flexible arms or holdersElectrode holder (sold separately) snaps on for holding an electrode, reference electrode, and ATC probeFlexible arm: 46 cm (18") long x 2.5 cm (1") diameterSturdy base: 23 x 16 cm (9 x 6"), weighs 1.5 kg (3.3 lb)Includes three reducing bushings and five nylon cable ties