Big rectangular picot has to be done by pre-cutting the fabric using S-1723 (strip-cut)
in order to make loose the fabric. Then the next step is to use the S-1720.
S-1723 is a high-speed machine and the S-1720 is a low-speed machine. It is recommended to use 1 set of S-1723 and 3 sets of S-1720 for most optimum result