"The safety rail locks automatically when in the upright position. Safety 1st Bed Rail 90cm is designed to help your child make the switch from cot to bed. ?Making it very safe and simple to use, with easy access to the bed when folded down. This bedrail can be fixed sturdily thanks to the wide frame. It will keep your little one from falling out of bed, while the see-through net allows you to watch him/her sleeping. 90cm in length and 41 cm in height. Suitable from 18 months +. Compatibility with mattresses-for mattress lengths up to 140cm."