product manual:
Applicable to the Tarot 550/600 helicopter model, laser mounting position of the spindle limit ring for easy installation of the main sprocket screw.

Product specifications:
Spindle × 2 (Φ10 × Φ7 × 192.6mm) 58G
Limit ring × 1 (Φ19.5 × Φ11 × 6.5mm) 3.1G
M3×16MM cup head hex screw ×1
M2.5×10MM cup head hex screw ×1
M3×5MM Hexagon Screw ×1