Car guys building street machines, this JEGS torque converter is perfect for your GM TH350 or TH400 transmission! The 12\ size with 10.75\ bolt circle delivers a stall speed between 2300-2700 RPM, which is ideal for moderately modified street vehicles. It's economically priced but still built with quality that can handle your weekend cruiser or daily driver. The street stall design provides that nice launch off the line without being too aggressive for street use. Just keep in mind - this converter isn't designed for nitrous, turbo, supercharger, or big block applications. It's meant for naturally aspirated small block builds where you want improved performance without going full race spec. Installation is straightforward if you're familiar with transmission work. You'll notice quicker acceleration from stops and better overall drivability. Perfect for that Chevy project car or truck you're building for street use and occasional showing off. JEGS has been serving the performance community for years, so you know you're getting quality parts that deliver what they promise.