We have a small SIGG bottle for water. I was told the top spout part and cap can be run through the dishwasher but that the bottle part could not. So I've been handwashing it by using my finger with soap to get as far into the bottle as possible and then swooshing around soapy water inside.

But I'd like to find a bottle brush that can fit inside and thoroughly clean it. Our avent one doesn't do the job (too large to fit inside!).

Any suggestions?