Convert standard 2.1mm to 2.5mm (for LINE 6, Whammy etc.). One 2.1 female socket, 1 male right angle 2.5mm plug; about 3" long.
Used to power 2.5 pedals thru PedalSnake PLines. These pedals often require their own 2.5 power supply.
NB - LINE 6 MODELERS, if powered from a standard center-negative 9VDC supply (like Dunlop Brick), also require 21RP (reverse polarity adapter). If powered by the LINE 6 supply through PedalSnake, use only 2125AR for the pedal and 2521A for the supply (at the Amp End of a PedalSnake PLine).