... :1) aluminium or copper rings2) with or whithout silicone3) 3.5MM X2MMX2MM ,3.4MMX3MMX6MM, 3.5MMX2MMX6MM2.8MMX2.3MMX7MM etc4) different color : Brown,light brown ... /weave,clip in hair extension,pre-bonded hair extension,U,V,flat tip hair extension,stick hair extension,loop ring hair extension,tape/skin hair ... brand. Choose me ,your best choice to save you budget.and gain more profit.