Stahlwille University
Stahlwille spline is designed specifically for gas turbine repair work. Cold forged from Stahlwille's special blend of HPQ material these are spline tools that are built to out last all others. Thin walls, chrome stable and dimensionally accurate, these are the hallmarks of Stahlwille tools.
All of Stahlwille's spline tools are cadminum free meaning they are safe for titanium fasteners presenting no corrosive effect. Stahlwille spline meets MIL-SPEC, DIN, ISO and aerospace specifications.

Be aware that some competitors are selling DIY (Do It Yourself) "universal" spline to aerospace customers. This spline is NOT Mil-Spec and can cause some significant problems and damage to fasteners especially in high load carrying situations. This Universal spline is typically sold as working on 6 point, 12 point, hex, and square drive nuts as well as spline fasteners. Buyer beware.
Stahlwille HPQ is a special type of "spring" steel. This allows for amazingly thin walls and 1/3 higher load carrying ability than standard tool steel.