These 3/8-24 stainless jam nuts are available in convenient packs of 50. Dimensions are as follows: Width (flat to flat) is 9/16" & thickness is 7/32". 3/8-24 is considered fine thread because there are 24 threads per inch (tpi). Jam nuts are typically half as thick as standard nuts and are useful in tight space applications. Type 18-8 stainless steel is most common. It has a high resistance to rust and corrosion and may be mildly magnetic.