I posted earlier on the forum about how I found that the hat on the 450 K was "cramped". I noticed in the assembly manual that the hat mounting for the DTX400 (lower kit) was different than for the 450K . When I mounted the hihat on the 450K the same as for the 400 it gave me a little more clearance between the hat and the snare. Much better! Don't know why they reversed the assembly but if you have a DTX450 this works much better. I think I have solved my cramping problem.