| 165 / | HD | HEAT EXCHANGE |
| DIG 454 | DD | HAVING SIDE-BY-SIDE CONDUITS STRUCTURE OR CONDUIT SECTION {16} |
| DIG 500 | DD | .~ Side-by-side conduits with fins {2} |
| DIG 501 | DD | .~.~ Plate fins penetrated by plural conduits {2} |
| DIG 502 | DD | .~.~.~ Lanced {1} |
| DIG 503 | | .~.~.~.~ Angled louvers |