The GPM MZA0345SP coil spring set is specified for Kyosho Mini-Z AWD tuning, offering three precise wire thicknesses: 0.3mm, 0.4mm and 0.5mm. These sizes allow step changes to spring stiffness so racers and tuners can dial handling, roll and front to rear balance without altering other hardware. Springs are supplied for repeatable performance and stable handling characteristics when used in standard Mini-Z AWD suspension assemblies.