A surge protection device base comprising: a first housing comprising at least one first structure; a second housing comprising at least one second structure; at least one third housing arranged between the first housing and the second housing and comprising a first half side adjacent to the first housing and a second half side adjacent to the second housing; wherein the first housing, one or more third housings and the second housing are spliced together to form a multipolar surge protection device base; wherein the first housing and the first half side of the third housing adjacent thereto constitute a unipolar surge protection device base, the second half side and the first half side of two adjacent third housings constitute a unipolar surge protection device base, and the second housing and the second half side of the third housing adjacent thereto constitute a unipolar surge protection device base, wherein: the first structure corresponds to an element positioned within the first housing and the second half side of the third housing, the second structure corresponds to an element positioned within the second housing and the first half side of the third housing, through holes are formed in the third housing at corresponding positions, so as to install connected elements used for a multipolar surge protection device. a first through hole formed at a first end of the bottom of the third housing is configured to accommodate a connected bus bar, and a second through hole formed at a second end of the bottom of the third housing is configured to accommodate a connected microswitch. a first housing comprising at least one first structure; a second housing comprising at least one second structure; at least one third housing arranged between the first housing and the second housing and comprising a first half side adjacent to the first housing and a second half side adjacent to the second housing; wherein the first housing, one or more third housings and the second housing are spliced together to form a multipolar surge protection device base; wherein the first housing and the first half side of the third housing adjacent thereto constitute a unipolar surge protection device base, the second half side and the first half side of two adjacent third housings constitute a unipolar surge protection device base, and the second housing and the second half side of the third housing adjacent thereto constitute a unipolar surge protection device base, wherein: the first structure corresponds to an element positioned within the first housing and the second half side of the third housing, the second structure corresponds to an element positioned within the second housing and the first half side of the third housing, through holes are formed in the third housing at corresponding positions, so as to install connected elements used for a multipolar surge protection device. a first through hole formed at a first end of the bottom of the third housing is configured to accommodate a connected bus bar, and a second through hole formed at a second end of the bottom of the third housing is configured to accommodate a connected microswitch. the first structure corresponds to an element positioned within the first housing and the second half side of the third housing, the second structure corresponds to an element positioned within the second housing and the first half side of the third housing, through holes are formed in the third housing at corresponding positions, so as to install connected elements used for a multipolar surge protection device. a first through hole formed at a first end of the bottom of the third housing is configured to accommodate a connected bus bar, and a second through hole formed at a second end of the bottom of the third housing is configured to accommodate a connected microswitch.