Square shaped interlocking beads.
First three rows are 3mm size regular Bohemian molded beads. Courtesy of Jared Elbert collection.
Rows 4 to 11: These Prosser type beads are seen on a Risler card as Serie 5010 in three sizes 5, 6 and 7mm. They are also seen on a Redlhammer card as “Knebel” beads, Série 2019 in 6mm in 15 different colors pictured in Beads from Gablonz.