Racket mass displacement device for sports practice

A mass displacement device in a racket for sports comprising:

• a racket handle;
• a hollow main tube fixed by glue or other adhesive means to an inside of the racket handle, the main tube comprising:
• an external support flap and an internal thread at a first end;
• internal symmetrical guides formed along the entire length of the main tube and protruding from an inner wall;
• and
• a centralized concave receptacle at a second end;
• a cover having an external thread and a central hollow hole;
• a counterweight having an infinite internal thread and symmetrical grooves,
• a central stem passing through the central hollow hole of the cover and fixed to the cover by means of a clip, the central stem comprising:
• a protruding head at a first end;
• a smooth upper part adjacent to the protruding head;
• a channel around an entire circumference adjacent to the smooth upper part;
• a body with an infinite thread;
• and
• a convex part at a second end.