SAL electrolytic capacitor
SAL electrolytic capacitors (SAL meaning solid aluminum) are a form of capacitor developed for high capacitance in a small package, with a long and robust service life. They are aluminum electrolytic capacitors with anodic oxidized aluminum oxide as dielectric and with the semiconducting solid manganese dioxide as electrolyte.
Source: Wikipedia — SAL electrolytic capacitor (CC BY-SA 4.0)