Hi All, Many thanks to all the folks who responded to my request
for Simplex block valve units.
During the course of the process, I was informed that there are two
sizes: The regular blocks, for the more common 3-tier model, have
round pouches. The units for the 2-tier model have oval pouches,
and they are narrower than the 3-tier version.
Again, thank you to all who responded, and to the MMDigest for
working tirelessly to keep this fine organization operating. Don't
forget to make an occasional donation. :-)
John A Tuttle
Brick, New Jersey, USA