I bought 10 of the Jinsoku R flex iron shafts at $3 each. Today I profiled 3 of them from butt to tip, and all 10 on the last two tip measurements. This is using the Wishon type measurements with 454g weight, measuring CPM from 36" beam length to 11", in 5" increments. The numbers are: 207/228/275/342/493/833.
A quick look in the spreadsheet tells me the numbers are similar to Wishon S2S White R but this shaft has a bit stiffer tip.
The average torque of 3 shafts was 3.3 degrees.
Weights were evenly split between 74 and 75 grams.
All of the measurements were quite consistent.
However, if you care, it is a high balance point shaft. It says MBP on the shaft, but I measured.
From tip, 20.375". From butt: 18.625". Overall is 39". I don't think the shorter shaft accounts for the BP being high. Usually the shafts are about same weight per inch at the tip as at the butt.