I've been basing my models on 18mm in diameter and 1,2mm height washers from Bunnings Warehouse. But I found that for some models want to use smaller washers. I found 15mm washers and based some of my animals on them, but I wasn't satisfied with final result, because these 15mm washers are very thin, about 0.3mm in height.
But recently I found some new washers Bunnings Warehouse. These washers were sold not in packs but individually and have diameter of 15mm and height of 1mm. So I rebased my Eytaran on new washer.
Now have a look at infantry and cavalry model based on 18mm washer with Eytaran on new 15mm washer! At last they all have same style. If you interested why Rebel Minis marine and Ottoman general have bronze base sides and Eytaran base side painted with Kommando Khaki, here is the answer: I paint base sides of ordinary models with same colour as their bases sand, Unit leaders have blue base sides, squad attachments have red coloured base sides and army commanders have bronze base sides.
For big models I use 31mm washers.
P.S. Yes, I changed flock on Rebel Minis commander, so dont be confused why this model have different base on first and second photo.