RIO's Pip Squeak mouse is a killer pattern that has a following in the Alaska Leopard Bow and the night-ops Brown games. But this fly is meant for big trout and is usually fished with a 6 weight rod or more. RIO's Pip Squeak Baby 25% smaller and can be fished to average sized trout anywhere with 4 and 5 weight rods. If you've never tried fishing a mouse before, do yourself a favor and skate or skitter this along grassy banks, log jams, shallow riffles, or anywhere you think a trout may be lurking. It's incredibly exciting and fun.