I bought a Teleconverter for my RB67 from KEH which was rated EX and it appears to be new and has both caps which also appear to be new. $49.00 and the optics are great. I have one for my Mamiya 645 and can remember only using it once but since I have a 180mm lens for the RB and don't expect to get more lenses, I have the 90mm and the 180mm, I thought I would try it with the 180mm to get 360mm. Anyone use one of these on an RB? BTW they are back on line.