A flagpole spinner avoids furling, that is prevents the flag from tangling or wrapping. The banner flying in the wind is glorious to see, but is difficult on a windy day. The flag can become stuck around or over top of the flagpole.
Furling options to prevent this include using some type of spinning unit, a rotating pole or collar device for the flagpole.
Furling kits are available as kits with ball-bearings for a section to move. And top half spin poles with the bottom half stationary.
Or a larger pole may slide over an inner pole, like a sleeve, that rotates in the wind to prevent a tangle.
Using collars above and below on the flagpole attached by rings allows the flag to move around the pole that remains stationary.