I've been given a manual Avent breast pump by my sister, who didn't ever use it (she also bought a Medela Swing thing, and only used that herself). Avent don't seem to make make bags for freezing breast milk, so I'm not sure what to buy to use with it. Bags are my preference, so has anyone used another brand of bag and found they fitted with an Avent pump? Baby isn't due for another three weeks, so I haven't got anything to do trial and error with yet... (but hoping to avoid purchases that won't turn out to be compatible).