| 摘要 |
Forceps consists of two connected arms at their upper ends, made of plastic or stainless steel. Its total length ranges 18/20/22 cm, width of each arm is 0.3 cm at its lower end and 1 cm at the upper end, thickness 0.2 cm, outer surface has transverse ridges in its middle third and smooth inner surface. The lower end of each arm is connected with the middle of the closed end of an inverted - U or semi - oval shaped structure. Its height is 2 cm, width at the open end 1.3 cm (0.2 cm width of each limb or inverted - U, 0.9 cm for distance in between). Its inner surface is rough (has criss - cross striation) while its outer is smooth. Connection angle between the inverted - U and forceps arm is either 0 or 25 or 45 degrees. |
