does the central body is also provided with a plunger assembly to act as a braking mechanism for the bobbins when necessary and as directed by existing sewing machine components and conditions a hammer 41 is activated the hammer is connected to a plunger 43 which extends beyond the central body and presses firmly against the left hand bobbin casing this serves to stop any rotation of the bobbins since the small gap between the bobbins is eliminated as the bobbins bear against each other and the bobbin casings such hammer and plunger activation may occur for example during bobbin rotation to maintain bobbin thread position at the appropriate moment again dictated by the existing sewing machine parameters the hammer is released and the plunger spring 42 causes the plunger to retract back into the central body the butterfly wing stabilizer clip slides into a mounting boss 44 and the entire unit is secured to a bracket 26 by means of a threaded stud and nut assembly 45 the clip is in turn attached to a leg of the sewing table by any ordinary attaching means including nails screws etc since the butterfly wing stabilizer clip is spring loaded it exerts a pressure against the left and right hand.