The elastic at the top allows you to clamp the net around the rim of a nappy bin and when it is full, put the net in the washing machine. During washing, the nappies fall out of the net so they get clean properly.
Compatibility
Useful for 40-45 litre buckets. Of course, smaller is also possible, just hang a bit of net on the bottom :-)
Tip
2 laundry nets are preferable, 1 in the laundry, 1 in the bucket!