This stops them both from being damaged by being stored separately.
Inside the main tube is a boss, this keeps the rubber top cover in place to stop any sideways movement in the tube. The top cap has a boss to keep the ATAS120a central. The ATAS120a, when inserted correctly is in suspension between the bosses so that it doesn't touch the tube walls.
Finally the bottom cap closes a section separate from the ATAS chamber which can store hex keys, grub screws etc ( you need to put the grub screws in a small container. This chamber is approximately 41cm (16 inch) long and 50mm (2 inch) diameter.
The 3D printed parts are made from PETG Polyethylene Terephthalate which is similar to what plastic drinks bottles are made of and TPU. The metal tube is aluminium and the main tube is PVC, polyvinyl chloride.
If you have any questions then please do contact me.
Buyers outside of the UK will need to send me their email address and telephone number for shipping.
This is NOT a Yaesu product. It was designed and manufactured by myself.