Oh, I understand the crossing of terms, but this is what OP said.
"I am looking at the OMS SMB which provides about 50# of lift OMS Lift Bags & Surface Marker Buoys OMS Official Site - Technical SCUBA Equipment http://www.OMSdive.com. This seems like a reasonable approach in that it provides plenty of lift and the desirable SMB function."
The link is a DSMB, tube.
In reading the entire thread, I see that Web Monkey probably was in fact speaking of a lift bag.
It was a great thread by the way.
"I am looking at the OMS SMB which provides about 50# of lift OMS Lift Bags & Surface Marker Buoys OMS Official Site - Technical SCUBA Equipment http://www.OMSdive.com. This seems like a reasonable approach in that it provides plenty of lift and the desirable SMB function."
The link is a DSMB, tube.
In reading the entire thread, I see that Web Monkey probably was in fact speaking of a lift bag.
It was a great thread by the way.