OME 864 1.5" on ARB pdf file???

[Peluo]

I have this springs OME 864 extra heavy duty. I was looking at the PDF file from the ARB website and they say there "Heavy Constant (880lbs to GVW) Spring 1.50" 1 2864" wow is that a typo? when i bought them from Slee a few years ago they where suppose to be 2.5". I am looking for some hire lifting springs for overlanding, but i don't want to 4" maybe 3"-3.5" max. Here in Caracas i can get King Springs and they are listed in there catalog as:
EHD PLUS (300-500KG CON LOAD) front KTFS-94HD rear KTRR-70HD
SUPER DUTY PLUS (500-750KG CON LOAD) front KTFR-69HHD rear KTRR-70HHD
KTFR-69SP3- 4 - 5 & 7 KTRR-70SP3- 4 - 5 & 7 SPRINGS AVAILABLE FOR L/CRUISER 80-100 SERIES
I guess that means that the HDD are in 3",4",5" and 7"
that is some serious wait capacity, i bet they unload with some force.
Question is this INCH game is driving me