This is located in the cast aluminum or steel cased tensioner bracket.
The tensioner arm slides into this sleeve/bushing and keeps the hole in the aluminum bracket from becoming "wallowed out".
Without this sleeve/bushing in place the shaft will be canted at an angle.
Eurovan 1992-1996 If the L-shaped tensioner lever appears to be crooked or angled out of alignment, this sleeve is most likely worn out. IOW, if your serpentine belt tensioner roller appears to be not aligned with the rest of the pulleys and rollers, this is most likely the cause.