Size small is for pets up to 13" L x 7.5" H and up to 8 lbs.
Measures 15" L x 10" W x 8.5" H

Approved by almost all airlines as an under-seat carry-on. Highly regarded for years.

Delivery only. Pick-up not available. Sold by Walmart.

Free shipping starts at $ 35, so you’ll need some filler. 90-day returnable to store.

https://www.walmart.com/ip/seort/464396889

Amazon is matching the price in "frustration-free packaging," but one review from 2017 says you might get a knock-off: