Zipped mesh bags are made from a durable mesh fabric - hole size of a pencil point which will contain small items within the bag. This is ideal for washing delicate items or items with parts which may come off or get trapped in the machine (for instance bras).
For normal laundry we would recommend our net bags (which have a hole size that a pencil would pass through) and allow larger particles to be washed out.
These bags are much stronger than the cheap mesh bags that are commonly available and are suitable for commercial use.