Shovel Base Sign Stands are popular as temporary promotional fixtures because merchandise placed atop the Shovel Base anchors the unit. Tall sign extensions are then possible and stable. Most Shovel Base Sign Stands are threaded taper lock adjustment. This design is of a ratchet variety I had not seen before. Reminds me a bit of an old Chevy car rachet jack I once owned, but this implementation far more modern.

To follow sign stands and arms see…
Dior Table Stands Are Floored
Religiously Inspired Sign Holder
Huge Sale on Bigfoot Socks
Gucci Scarf Now Only $250
Lyre-shaped Sign Stand
Sophisticated But Simple Signing
Sign Circle: Table Stand
Shelf-Edge Spoon Sampler Spirals
Uglys Point-of-Purchase Stand
Arm for Circular Foamcore Sign
Ratcheting Shovel Base Sign Stand
Stanchions as Selling Tools
Sign on a Stick.”