Terminal block and terminal block unit

A terminal block unit comprising:

• a terminal block body including one or more terminals each having two ends serving as electrical connection points;
• and
• a case including an attachment portion to which the terminal block is attachable, wherein:
• the terminal block includes:
• a terminal block body configured to be attached to the case by being fitted to the attachment portion;
• and
• an annular elastic seal arranged to seal a connection between the attachment portion and the terminal block body,
• the terminal block body further includes a protrusion configured to press and fix the elastic seal against a flat attachment surface of the attachment portion without moving the elastic seal in an attachment direction during attachment to the attachment portion, and
• the elastic seal includes a compression portion configured to be squashed and pressed against the attachment surface by the protrusion during attachment.