iPad Pro 12.9 Sleeve

Honestly, you want a sleeve slightly larger than the iPad. I have a Fintie for my iPad Pro 11 and it's also slightly larger, but it fits perfectly, has a little extra room for my Apple Pencil or cables, etc.

Here's the Fintie for the iPad Pro 12.9: https://www.amazon.com/Sleeve-Diamond-Ripstop-12-9-inch-Pencil/dp/B06XC252NZ/ref=pd_lpo_vtph_193_tr_t_2?_encoding=UTF8&psc=1&refRID=5WB759P2TZE1PJZMKJS2

Here's my iPad Pro 11 looks in the one I purchased:

Here's another sleeve, which will work for your iPad, if you want to spend a little more and have leather, from Brydge: https://www.brydge.com/products/13-inch-leather-folio

You're very welcome.