Collin Tracheotomy Fig mm 0 4 Y17.170.04 1 5 Y17.170.05 2 6 Y17.170.06 3 7 Y17.170.07 4 8 Y17.170.08 5 9 Y17.170.09 6 10 Y17.170.10 7 11 Y17.170.11 8 12 Y17.170.12