Thumb screws make for easy hand adjustments as they are designed to be turned with just your thumb and forefinger. Fully adjustable, they offer a wide variety of household and mechanical applications. The variants included in this Metric Thumb Screws Assortment run M5-0.80 thru M8-1.25 in USS coarse thread size. Parts all feature a spade head style. Full assortment contains twelve (12) refills comprised of Hillman item numbers #45140 - #45151.