| 摘要 |
The present invention is provided with: a protruding part for piercing the skin, the protruding part having a through-hole passing through the protruding part in the direction in which the protruding part extends; and a cylinder part having as an end surface a support surface which is a flat surface supporting the protruding part and which is configured to press against the skin, for supplying a fluid to the through-hole of the protruding part. Where the length of the protruding part in the direction in which the protruding part extends is designated as length H, and the surface area of the support surface is designated as surface area S, the ratio of the surface area S to the length H (S/H) is 2.1-10.5, inclusive. |
