I have father foolishly managed to melt my medela swing breastshield while sterilising it in a steamer (definitely going to buy a microwave now)!
I'm really strugging to source replacement parts as it seems the part I melted is no longer made and the shields are now personal fit. So I need to ask a potentially stupid question but how do I know what size to buy? I'm not exactly well endowed so likely to need small 21mm or standard 24 mm but not exactly sure what the measurements are based on, can anyone advise?
TIA.