Waterproof trousers are going to be to your most outer layer serving as long-lasting protection from wind and rain, these trousers will continue to offer the breathability you need when out on the hills. Waterproof trousers come in two types 2 layers + trousers or overtrousers; 2 layer+ trousers have a permanent waterproof outer which will keep water from seeping through and is made with a highly durable and breathable fabric that prevents abrasion letting you wear these during any activity from walking to scrambling and they won't let you down. Whilst the inner fabric will insulate your legs with a mesh or fleece lining to also keep you warm, perfect for colder days when it's looking more than likely to be wet. The other type of trouser is waterproof overtrousers these are a great addition to your walking pack, being able to pack down small in your pack and can be worn over any trousers when the rain starts for complete waterproof protection. With adjustable cuffs to help pull up over your shoes and stop rain coming up your leg, whilst an elasticated waist can fit over your trousers. Then when the rain has passed, they are quick to dry and can then be packed away again for when the next rain shower starts.