Can this be used as a booster seat or is it only able to be used with 5 point harness?

Hi Rachael, Thank you for your enquiry. Unfortunately this seat is not designed to be used as a booster seat. It is for use with a 5 point harness from birth to up to 29.4kg (approx 4-5yrs depending on childs weight), with a height limit of 124.5cm (49 inches). If you follow the link https://www.babyonthemove.co.nz/store-locations/ this will take you to our online store finder where you can find contact details for your nearest Baby On The Move Store. Here, one of our expert Car Restraint Technicians can assist in helping you to find the right car seat for you and your child. We hope this has helped with your query.