Short Green Stream Thermometer With Ring- Read the water temperatures with this essential thermometer. It's important to know the water temps all season long, especially when trout fishing. It helps anglers learn and be aware of what the optimal temps and not so optimal temps are (when fishing for coldwater species an angler needs to be aware that once temps rise above the mid 60's it begins to create problems and may be lethal to Mr. Fishy). Encased and protected for durability. It can be easily accessible with key ring attachment that clips to a zinger. 4 1/2".