Copied from another thread:
Woollywraps are machine washable on a wool cycle (others are up to you if you wool cycle em... I do tend to though )
Soak them overnight in lanolin (you can either buy a ready made solution or I can give you very step by step instructions if you buy solid lanolin).
Let them dry, then use them each night, air them during the day in between.
If not soiled, don't wash them until they start to retain a smell after airing.
When they do start to retain a smell, bung em in the machine on a wool cycle with a squirt of baby shampoo.
Resoak in lanolin.
You resoak after each wash for the first 3-4 washes, after that just do it once a month or so.
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They work (as far as I know... could be talking gibberish) by the wetness forming a soapyness with the lanolin, hence the self cleansing thing.
The lanolin helps keep them waterproof so they absorb wetness and it doesn't pass through to the clothes whilst it evaporates away.
You need to relanolise to keep the waterproofness and the self cleansing.
Lanolin allergy is quite rare.
Dry away from direct heat.
Easy and less washing than other wraps!