Electronic unit

An electronic unit comprising:

• a case including an opening;
• a circuit board housed in the case;
• and
• a cover attached to the opening, the cover including a hood having a through hole,
• wherein a connector is provided on the circuit board,
• a portion of the connector to be connected to a mating connector is exposed to the outside through the through hole,
• a set of a first clearance portion and a second clearance portion is provided in a first position located between the cover and the case at a position of the opening and is continuous with the opening, the set of the first clearance portion and the second clearance portion is provided in a second position located between the cover and the connector at a position of the through hole and is continuous with the through hole, or the set of the first clearance portion and the second clearance portion is provided in each of the first position and the second position,
• a clearance in the first clearance portion is larger than a clearance in the second clearance portion,
• the second clearance portion is located on an inner side of the case relative to the first clearance portion in a direction in which the circuit board is inserted into the case through the opening, and
• the first clearance portion extends and reaches the second clearance portion while maintaining a constant clearance.