Basically the Bottle systems concept is similar to other spaceframe connectors design that comprises of Front part (the Bottle-body), the Rear part (Plate) which is welded to the pipe/member and its Bolt, with the exception that this system has an additional spring to lock the Bolt-body keeping it tightly with the Rear-plate.
Rear-plate. The trumpet-shape of the Bottle-body is also the specific feature of Space.co._Steel Bottle system that not only has a cylindrical, nice appearance but it will also transfer the compression force smoothly from the small-end of the Bottle-body to the larger part preventing any buckling effect to the plate.