Tunnels are made with 100% stainless steel, gold with PVD electroplating.
Highly polished, with no screw on back.
The back is shorter than front, you need to put the back in first.
Size:
6 mm (2 g); 8 mm (0 g); 10 mm (00 g); 12 mm (1/2 ''); 14 mm (9/16 ''); 16 mm (5/8 '').
Each piece is measured by hand. Please allow for minor errors.