YaeTek 110V Full Set Jewelry Jade Pearl Stepless Drilling Holing Machine Driller Tools – Pearl Drilling Machines Driller Drill Holder for Shell Coral Amber Stone Silver * Used for accurate holing on such precious stone as pearl, coral, amber and ornaments components such as gold, silver and copper. * This machine is equipped with 9 suits of special collets, which is suitable to the pearls in round shape, “ж” shape and other shapes or special shapes. * Control collet and rotation of pearl by using rotary handle, easy and highly efficient. * Collet of this machine is made from nylon, which prevent pearl from being mingled with flower and scar. * Can make a hole on pearls of various specifications from Φ3 – Φ25mm (including fresh water pearl, seawater pearl, south sea pearl, Daxidi black pearl, shell, coral and amber).