Original Curtis Turner convolute (not filament wound) carbon fiber airframe, 48" long 4" diameter. Price on these when PR was still in business was $180, asking $150 OBO plus shipping.
I recognize that tubing, I have it in a 54mmx60" and 54mmx24", and a 9" coupler. The plan is a Loki 54/4000 case with the L2050 and the M1378 in a 54mm min diameter with this tubing...however that plan is not likely going to take place for a couple of years. One thing for sure is that it is heavier walled than any other commercial CF tubing I have seen and it is surely up to the task of the abuse that those motors can hand out.