Standard 3/8-16 steel zinc finished Hex Nut commonly used on leg levelers and other hardware
Willliams part #4422-01127-00 , Gottlieb FA-665
Used on the following games
Medieval Madness , Dirty Harry , Jackbot Jack bot , Indiana Jones , Hurricane , The Getaway High Speed 2 , Flintstones , Fish Tales , Bram Stokers Dracula , Demolition Man , The Machine Bride of Pinbot , Johnny Mnemonic , Star Trek the Next Generation , White Water , WhiteWater , Tales of the Arabian Nights , Bad Cats , Pool Sharks , Attack from Mars , Black Rose , Corvette , Truck Stop , Elvira and the Party Monsters , Mousin' Around! , Transporter the Rescue , Theatre of Magic , Who Dunnit , Game Show , Pinbot , Grand Lizard , High Speed , Comet , F-14 Tomcat F14 , Millionaire , Space Shuttle , Sorcerer , Road Kings , Banzai Run , Big Guns , Cyclone , Diner , Fire , Space Station , Swords of Fury , Taxi , Police Force , The Machine Bride of Pinbot