Signature Climber's Cap

I purchased Isadore cap couple months back (different one from previous series) where only one size of the cap was available. As my head is a bit on a bigger side (59-60cm in diameter) the previous one was bit small. Once helmet is on, there is that tightness from helmet so I am OK with the cap under helmet but having just cap on the head was not 100% comfortable. So once these new series of caps arrived which is now offered in 2 sizes I thought that the bigger size will be now really bigger than previous version plus the materials used are more elastic. The reverse is true though. It is even tighter on my head than the previous one so I will have to return it. In any case it is a beautiful cap, nice colours, great materials used, I just wish it was 1 cm larger in diameter.