Here is a vintage clear glass double jigger measuring 4 and 3/4 inches tall. There is no maker’s mark.
This jigger is marked “2 OZ” at the top of the larger side and “3/4” below that with a line to mark the measure. The smaller side is marked “1 OZ” at the top with “1/2” lower down and a line to mark the measure. There is a bulbous belt running around the middle.
This appears to be a two part mold as there are seams on opposite sides.
I am estimating this dates to the 1960s but it could be older or newer, I just don’t know.
A functional, attractive bar tool, for sure!
This jigger is available for sale here at my Etsy shop: https://www.etsy.com/listing/643224718/clear-glass-double-jigger