This is the only known example of this one-of-a-kind maker's mark.
The mark is impressed into the glass and looks like a 'Z' with an extra bar. It is definitely not a double stamp.
This float is 9 3/4" in circumference and 3" wide.
It's completely frosted.
This float was found by Paul Umlauf on a remote Aleutian beach in Alaska.
It takes two floats to verify a maker's mark, so if you have a float marked with this stamp please let me know.