Patent ID: 11180277

Abstract:
A body portion (120A) that is a cylindrical body has one end portion, such as a lower end portion or the body portion (120A) or a first part (126) of a body portion (120), that is folded back inwardly. The body portion (120A) has at least one planar-shaped flat section, such as a second flat section (122) or a fourth flat section (124). A notch, such as a notch (K1) or a notch (K2), is provided at one end, such as a lower end, of the flat section. The one end portion includes a portion provided with the notch, such as by providing the notch (K1) or (K2) at a lower end of the lower end portion of the body portion (120A) or at a distal end of the first part (126A) of the body portion (120).