This shows the carbon fibre focuser platform that the Optec TCF-S3 will be mounted on. The yellowish filler is an epoxy / filler that will be oven cured as well. The focuser hole will be around 90mm diameter.
The tube itself is of sandwich core construction. It has a honeycomb core that is 5/8" thick and 2 layers of carbon fibre on both the inside and outside tube walls (4 layers in total). This (combined with the inherent properties of carbon fibre) yield a tube of extremely high stiffness.
This is being made by Dream Telecopes & Accessories in the US and should be shipped in the next few weeks.