摘要 |
<p>The holder (20) has a ring body (201) with fastening rings and slip rings, where the fastening rings are attached to front and rear sides of the slip rings. Slots are located in inner surfaces of the fastening rings when the slip rings are provided with fastening holes. A steel ball (30) is located in the slots, and a detector (203) is located at an upper end of the ring body. A base (202) is provided with two ends, where one end is provided with a connecting section, and another end is provided with a locking section. The connecting section and the ring body are connected with each other.</p> |