Design for Nikon J1 J2 J3 J4 J5 V3 S1 S2 AW1 LensAutomatic Extension Tube Set is combined of 2 rings-10mm,16mm.This is used by attaching between camera body and lens of the mirroless camera. It comes as a set of 2 tubes of different lengths in single or combined use.It couples perfectly with the camera's automatic diaphragm with cameras of TTL.AE (Through-the-lens, automatic exposure) type it gives perfect coupling except when combined with electronic flash AE unit. 
