Interesting version of mark WP #24 'Shi' シ. In this stamp all of the elements of the shi symbol are left aligned.
This version of the mark was quite uncommon until about 2020 when many more of them began to show up for sale. Now, they are common finds.
The float measures about 2 1/2 inches in diameter.
Excellent provenance having been part of Michelle & Shane Konkle's first big container of floats from Japan in 2021.