Whiting Farms Whiting W 100 Hackle Gauge Color:Slate With a variety of double density FA6405 MD With a variety of double density sinking rates and a smooth While we have retained the aluminum handle not to a line* Designed to fit most popular 3 8" diameter fly tying vise shanks* Extremely accurate and consistent measurements with lasered scale* Each measurement has a dark and light bar to easily see any color of hackle* Goes down to size 28 (the diameter of the nail head pin is size #28)* Goes up to size 8 (the width of the entire hackle gauge is size #8)* Exclusively from Whiting Farms The Whiting Hackle Gauge gives the tier an all new method of measuring hackle for dry fly tying