Gaitors, which are like old fashioned spats, will help protect the waders since they help keep gravel out of your wading shoes. T here are various thicknesses of neoprene. A heavier, and lighter version is also made. Dive and wet suits are made of neoprene. It acts as a barrier from the cold.
S tanding in the ocean, or a river is cold.
Even colder before dawn and after sunset. Keeping warm makes sense. You can wear sweats under waders for extra protection if the 4.5 mil are too warm for your climate. Sweats do keep condensation from forming and making you look and feel like the waders leaked. W aders that fit your body closely are less resistant to current and waves.