I checked tp-link site https://www.kasasmart.com/us/products/security-cameras/kasa-spot-pan-tilt-ec70

and it states the following: 

Save your footage on a Micro SD card (up to 256 GB, sold separately) and playback with your Kasa Smart app.

I wil go ahead and buy a 256G card and post here if I run into formatting issues due to card being too big.