The ancient (Came With The House™) Electrolux canister vacuum cleaner long ago lost the plastic bushing around the opening passing its retractable cord, which I’d long sworn to replace. A recent trip around the Basement Laboratory paused near the recently relocated Box o’ Wire Loom & Braid, whereupon I snipped off a few inches of split loom and tucked it in place:
Looks and works better than before, anyhow.
The blue flap dangling off the back should latch over the exhaust port, but failed long ago when the latch tab eroded. I attempted a repair, which never worked quite right, and won’t get around to attempting another for quite a while.
The Smell of Molten Projects in the Morning 
“the exhaust port”
Any filters or is it just recycling “stuff” into ambient air? Wheels!!! The Rocking 70s and Era of Progress…
https://en.wikipedia.org/wiki/HEPA#Vacuum_cleaners
The bag is the only filter, but it keeps big chunks from blowing out the back. The thing definitely predates the era of consumer-grade HEPA filters!