| Reference Number | TPC/5/7/12 |
| Title | General Arrangement of Patchboard for Lower Theatre - National Theatre |
| Level | File |
| Date | 08 November 1973-13 July 197[4] |
| Description | Evershed Power-Optics Ltd drawing number V4318, unnumbered issue and issues A and B. |
| Extent | 4 drawings |
| Series | Evershed Power-Optics Ltd Drawings |