what about the size ? I usually wear 45, will be 46 size OK for me ?

Merrell boots are utter garbage. I got a pair they replaced UNDER WARRANTY because the first pair had broken off half the lugs on the sole. THe replacement boots fell apart about two months after I placed them in service. I walk on GRASS. GRASS. County gravel roads. Once or twice a day. And they already fell apart. I contacted Merrell again and they refused to do anything about it. They were Moab's. They were $130.00 for the pair. That's $130.00 down the TOILET. I've been wearing them with the sole half fallen off cause they're useable during DRY, NON-DEWY, weather. But they have also developed a CHUNK on the outside of the inner sole, on the opposite side of my foot from the inner arch, that makes my outer foot ride up, and it really hurts. ALSO, there's no way to waterproof them. If you walk in twenty feet of dewy grass, your feet will be wet for the rest of the day. I contacted Merrell to ask what they used or sold to waterproof them. THey DID NOT. I asked them what they'd recommend to waterproof them. THEY DID NOT. They leak like sieves. Plus with the broken lugs on the bottom, any moisture that can, will get in through the outer soles. THey are JUNK. DO NOT BUY MERRELL BOOTS. \\ A $5 pair of Columbias I got at the thrift store lasted FIVE YEARS until I literally wore everything off the bottom sole. THey're still solid boots, and I use em for wading while trout fishing.