All HENRYS Yo-Yos are equipped with QUICK-TRICK system, which is the amazing innovation in the field of yo-yo playing. The gap for the string is getting wider or smaller by simply twisting both shells slightly against each other. Adjustable from up n down to loop mode or ultra-long sleepers for long-lasting string tricks. No annoying process of remounting or changing the axle. Dead simple and quick like lightning. The right adjustment for any trick..