First time with anal toys - concerned this inflatable plug doesn't have a flaired base, should it have?

I'm building a nogasm machine and as part of it I need to attach an inflatable plug, but I've never done anything arse-related before!

I also need to do this on a budget, so I found https://www.amazon.co.uk/NOPNOG-Inflatable-Dilator-Silicone-Black/dp/B0B9N7VL6Q/ but I'm concerned there's not a flared base as everything else I've read says anything going into the anal passage should have a flared base.

Is this design safe, or should I look at something a bit more expensive?