These are the 4mm Locking Wheel Nuts in Blue from JConcepts.
Fits all Traxxas vehicles that use 4mm wheel nuts as well as the
Associated SC10 4x4, and the TLR-22, TLT-22T and SCT-E, RC10B4 and
Precision CNC machined aluminum, flanged and serrated for added
Four 4mm Locking Wheel Nuts in Blue
7mm nut driver