Is seoltóir soladach copair shnáithe, bog é sreang TW/THW atá inslithe le Polavinylloride (PVC).
Seasann sreang TW do shreang theirmeaplaisteacha, resistant uisce.
Tá sreang THW freisin teirmeaplaisteach, sreang uisce-dhíonach, ach tá teas-resistant, arna shonrú ag an H san ainm.