question about ctl file using wgrib2

[amelia graziano]

Hello, hope someone can help! After I generate a ctl file using wgrib2
I get a strange word "none" e.g.:

./g2ctl -0 gfs.t00z.pgrbf00.grib2 > example4.ctl

all the lines in example4.ctl shows "none"

HGTprs   26,100      0,3,5 ** (profile) none Geopotential Height [gpm]
O3MR30mb  0,100,3000   0,14,192 ** 30 mb none Ozone Mixing Ratio
[kg/kg]
PRMSLmsl  0,101,0   0,3,1 ** mean sea level none Pressure Reduced to
MSL [Pa]

What is that "none"

Thaks a lot

Amelia