Protective element

A protective element comprising:

• a fuse element which comprises a blowout portion between a first end portion and a second end portion, and is energized in a first direction from the first end portion to the second end portion;
• and
• a case composed of an insulating material and having a housing portion housing the blowout portion therein,
• wherein a length in a thickness direction in a cross section perpendicular to the first direction of the blowout portion is less than or equal to a length in a width direction perpendicular to the thickness direction in the cross section,
• a first wall surface and a second wall surface that face each other in the thickness direction are provided in the housing portion,
• a distance in the thickness direction between the first wall surface and the second wall surface is 10 times or less the length in the thickness direction of the blowout portion
• a third wall surface and a fourth wall surface that face each other in the width direction are provided in the housing portion, and
• a distance in the width direction between the third wall surface and the fourth wall surface is 1.5 times or more the length of the fuse element in the width direction.