Dianne - my experience is that the Avent pumps are not great and there's
nothing more frustrating in an emergency than a pump that just wont work.
Test several of them on real mothers with real lactating breasts before you
buy.  Compare very carefully with other products.  I have used these for a
long time (when no others were available here) - now I don't any more.  I've
also written long, detailed letters to the manufacturers (Cannon Babysafe in
UK) letting them know exactly what problems I observed and how I thought
they could be remedied.  To no avail.  Sorry to be so negative, but you did
ask!

Pamela, Zimbabwe