| 52 / | HD | STATIC STRUCTURES (E.G., BUILDINGS) | 
| 415 | DF | FACERS; E.G., MODULES, MUTUALLY BONDED BY INTERNAL SETTABLE MATERIAL SECTION {13} | 
| 416 |  | .~ Lapped or bridger strip juncture-type surfacing {3} | 
| 417 | DF | .~.~> Dissimilar strip at juncture of facers | 
| 418 | DF | .~.~> Embedded fastener | 
| 419 | DF | .~.~> Material between superposed facers {1} |