Full Title

Vertical ducts; Channels, e.g. for drainage (pipes in general F16L; pipe-line systems F17D ) > for carrying away waste gases, e.g. flue gases (free-standing chimneys E04H12/28; connections between fireplace and chimney, chimney fittings, covers for cleaning holes of chimneys F23J; chimney tops F23L); Building elements specially designed therefor, e.g. shaped bricks or sets thereof