Did someone say another brand of teats fit medela bottles?

[cupcaker]

Due to starting off bf, then expressing, my baby is used to medela teats and bottles. Medela sell slow flow and medium flow, but I'm sure I read here ages ago there are other teats (e.g. Asda teats?) that fit medela necks, does anyone know? Just incase i can get hold of faster flow teats or generally cheaper teats if needed. Thanks