Main Rotor Linkage Ball H50094Instruction:Use for T-REX 500.Specification:Linkage ball A(M2x3.5) x 4(Φ4.75x8.18mm)Linkage ball B(M2x3) x 2(Φ4.75x9.77mm)Linkage ball D(M3x3.5) x 2(Φ4.75x17.5mm)