From Brotato Wiki
Esty's Couch is a unique item. Only 1 of each unique item can be equipped, and it will then no longer be offered in the Shop, and no longer drop from loot crates.
Esty's Couch provides a great amount of HP Regeneration, if you have low enough speed. The Couch only accounts for permanent changes to your speed, and doesn't includes the temperary decreases like the one Streamer gets while carrying materials.