FSN-21A-20 is a flexible jumper wire assembly manufactured by TE Connectivity/Buchanan Brand, designed for interconnection and wiring applications with configurable pin arrangements. The product features multiple conductor pitch options ranging from 1.00 mm (0.039 in) to 5.08 mm (0.200 in), with standard wire gauges from AWG 28 to AWG 24 depending on pitch selection. Pin configurations include straight pins (Type A), right-angle pins bent down (Type B), and various staggered pin arrangements (Types C through Z), with pin dimensions of 3.18±0.76 mm (0.125±0.030 in) for standard configurations. The jumper supports insulation lengths from 0.50 in to 30.0 in in 0.100 in increments, plus 0.25 in and 0.75 in options, with insulation materials available in Nomex, Polyester, Teflon, or Kapton. These flexible jumpers are commonly used in automotive, telecommunications, and industrial control applications where reliable interconnection with customizable bend configurations and conductor spacing is required.