We also found these shells, does anyone know what they are?

We also found these shells, does anyone know what they are?
Cartridge, 40mm AP-T, M81, M81A1 - Bulletpicker
This fixed ammunition is used in 40mm gun cannons for firing at armored and other protected targets. The projectile for the M81A1 cartridge consists of a hardened steel monobloc slug, crimp fitted on the blunt ogival nose with a thin steel, streamlined windshield cap to reduce aerodynamic drag

Source: Wartime Media - Ukraine / Russia / China / Etc
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