Reddit reviews 2-Qt. Nursing Bottle w/Screw on Cap

I really like Nuby Sports Sippers see Amazon link as they're real bottles for toddlers but an adult can suckle from them at a decent rate as they have a faster flow than regular baby bottles. They've been my go-to bottles for years.

Alternatively, if you're into animal play or just want a huge ass bottle, you could always go with calf feeding bottles. They have a rougher nipple texture, but you're not likely to find bigger bottles.