On Thursday, May 16, 2019 at 1:21:32 PM UTC-7, Discus 44 wrote:
I am looking for a replacement Qxygen cylinder for my ASW 28. It is the weird one almost the same size as a "D" bottle but smaller in diameter 4.125 inches and 16.5 inches long. Mine is stamped DOT-3AA2015 REE16.6 Which is the cubic ft capacity.

Check with Williams Soaring Center. Rex usually stocks steel tanks that will fit.