The dancing synchronization game MikuMikuDance uses SPA file to store model effects, such as hair and attire.
The file is saved as a BMP file with the SPA extension.
.spa File
Extension
Developer:
MikuMikuDance
File category:
What are spa files & how to open them - MikuMikuDance Sphere Mapping File
File category:
Developer:
MikuMikuDance