I did a search for "Lopez valve" on the web and found this page.

http://www.icumed.com/lopez-valve.asp

The picture they show there is very similar to the dohickey I have. Probably this IS something you could get from a medical supply store, though you might want a nurse to attach it for you, since it has to be really screwed in tight to the tube opening.

Nelie

SCC(T2N0M0) part.glossectomy & neck dissect 2/9/05 & 2/25/05.33 IMRT(66 Gy),2 Cisplatin ended 06/03/05.Stage I breast cancer treated 2/05-11/05.Surgery to remove esophageal stricture 07/06, still having dilatations to keep esophagus open.Dysphagia. "When you're going through hell, keep going"