Add the following:


{
"weightMultiplier": 0.1
}   


You can add it under the pounds:


"printer": {
    "name": "Zebra  ZP 450-200 dpi (Copy 1)"
  },
  "scale": {
    "manufacturer": "Fairbanks Scales",
    "productName": "Fairbanks Scales SCB-R9000",
    "vendorId": 2919,
    "productId": 21854
  },
  "scaleUnit": "lbs",
  "
weightMultiplier": 0.1
}