As a mummy of two little people under the age of two I have used a wide selection of different branded and own shop brand babygrows and bodysuits.

It never fails to surprise me how different the sizing can be from each store and brand (much like women's clothing).
Some have longer bodies, shorter legs, wider feet!

I've tried to make sure your ZIPPYUP is a good fit for your baby, the fabrics are 100% cotton and the basic babygrow is a 1x1 rib construction and weighs 320gsm for all the technical folk out there. The construction allows some stretch in the fabric without adding elastane which can make your baby hotter and the fabric less breathable. The zips are nylon and concealed to avoid any contact with your babies super soft skin. Baby onesies are a true essential, whether they are nightwear or daywear babies and movers get through them at a rate of knots.

All babies grow at different rates and are different shapes and sizes, just like us.
My youngest is now 10 weeks but somehow he is wearing baby clothes that are sizes 3-6 months. Maybe the hand-me-downs from baby boy #1 have completely shrunk in the tumble dryer and the many boil washes?!? Or he's a big baby and I'm feeding him up like a turkey.

In conclusion, all parents buy baby clothes that their little ones will grow into, we all want to get our money's worth.