| AIR ADMITTANCE VALVES Soil and Waste | DALLMER LTD |
| FERNCO LTD |
| HUNTER PLASTICS LTD |
| MARLEY PLUMBING & DRAINAGE |
| MULTIKWIK LTD |
| OSMA |
| POLYPIPE TERRAIN LTD |
| AIR ADMITTANCE VALVES Soil and Waste AGREMENT CERTIFICATE HOLDERS | HUNTER PLASTICS LTD |
| MARLEY PLUMBING & DRAINAGE |
| OSMA |
| POLYPIPE BUILDING PRODUCTS |
| AIR ADMITTANCE VALVES Soil and Waste BS EN 12380:2002 Kitemark | DALLMER LTD |
| FERNCO LTD |
| MARLEY PLUMBING & DRAINAGE |
| OSMA |
| POLYPIPE TERRAIN LTD |
| AIR ADMITTANCE VALVES Waste | DALLMER LTD |
| FERNCO LTD |
| HUNTER PLASTICS LTD |
| MARLEY PLUMBING & DRAINAGE |
| OSMA |
| POLYPIPE TERRAIN LTD |
