The 13mm Shock Collar Kit allows you to run 13mm springs on AE 13mm, TLR G3/3.5, and Schumacher LD3/L1R shock bodies. The kit includes 4 threaded shock collars that feature offset laser-etched Avid logos for ease of matching spring tension left and right in 1/4 turn increments with a silver ringer highlight machining.
Remember these don't come with spring cups so you will need to source those. AE does have 13mm spring cups (ASC91966) and 12mm spring cups (ASC91814).