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 . <EOS>