Telephone Code Index - 01591
| 620790 | Aggregate Industries - Builth Wells |
| 610473 | Cambrian Woollen Mill - Brecon |
| 610666 | Celt Ltd. - London |
| 610408 | Charcroft Electronics Ltd. - Llanwrtyd Wells |
| 610597 | Cyril Roger Davies - Llanwrtyd Wells |
| 620206 | D A R Jones & Co. - Llangammarch Wells |
| 620380 | Davies Graham John - Llanwrtyd Wells |
| 620413 | Dolfan Catering Equipment - Llanwrtyd Wells |
| 620412 | E W E Protheroe - Builth Wells |
| 610214 | H Buxton & Son - Llangammarch Wells |
| 610418 | John B Davies - Llanwrtyd Wells |
| 610445 | K W Norman - Llanwrtyd Wells |
| 610461 | Kenneth G Burton - Llanwrtyd Wells |
| 610618 | Leawell Technology Ltd - Llanwrtyd Wells |
| 610330 | Michael L Jones - Llanwrtyd Wells |
| 620641 | P W Jones & Sons - Llangammarch Wells |
| 620572 | Pigs Foley - Llangammarch Wells |
| 620610 | Satori Designs Ltd - Builth Wells |
| 620631 | T D & S J Gwillim - Builth Wells |
| 620260 | Violet Jones & Sons - Llanwrtyd Wells |
| 620438 | W J B Powell - Llanwrtyd Wells |
