I believe the seatpost brand is EC10SL but maybe it's ECIOSL. Either way, I have a picture below so you can see how it can be confusing. Stay away from any of them, no matter what size or configuration. I should probably go make a specific post about this. I bought 2 of them in different sizes and they both had issues.
Not pictured is the 31.6mm post I bought for my road bike. It kept slipping no matter how much torque I put on it. When I put calipers on the post, I discovered it was WAY undersized. I don't remember at this time what it was, but I remember thinking that I wouldn't be able to make it work without some kind of sleeve.
The one that's cracked (picture below) is a 27.2mm post that I put on my gravel bike. It measured right on the money for diameter and never slipped. However, on my first ride it cracked on a big bump (nothing crazy, just a big bump).