I received some brushes at the end of January and this olive wood Zenith boar was one of them. I have been gradually breaking them in by soaking in water but never more than halfway up the brush to make sure I wasn't soaking the actual knot in the handle. I came home and the brush was next in rotation and I see the split. Not sure what to use but would some CA glue stabilize the wood?It doesn't seem to want to be clamped back together. I contacted the seller and hopefully something comes out of it...sigh.