Here is a photo of the Goodnature A24 on my weighing scales.
As you can see the photos the trap in it's box is: 0.78Kg. Note, this is the Goodnature A24 with Counter on post office scales.
Here is a ruler showing the length to be 21cm
And length on one side to be 16 cm.
Finally, the length of the trap with the canister is around 21cm