Has anybody actually used the Please login or register to view links? This is the one that allows the aperture to be set on the Pentax DA lenses. Specifically, can anyone tell me how much it weighs? The only seller in the US seems to be Adorama - and neither Adorama nor the Kipon are showing a weight specification on their website. I am trying to decide between using this with my Pentax DA 70 mm F2.4 Limited - or - buying the Fuji XC 50-230mm f4.5-6.7 zoom, and I'd like to compare the total weights before I decide.