I bought the kit because I needed a new spindle and I thought I had a few bad ball bearings in my old grips. My LHS had the kit in stock so it was more cost effective to buy the kit instead of 2 sets of bb and a new center hub for the spindle. and the rest of the parts needed for the upgrade. Would have end up costing me about $50 to do the upgrade and fix the parts that I thought were already bad in my heli