My smallest is 5' 5" & 158LBS and is 17. She swings a 33 23 -10 Louisville Catalyst (the yellow one) my biggest girl is not tall at 5'8" but is 184LBS (farm girl) She hit with an Easton Stealth Clarity that is 34 23 and -10. Our league use Worth Red Dot Optic yellow 12" balls and are core .47 and 375LBS. These girls average 62 - 66 MPH ball speed of the bat from a tee. We get this by having them do six swings; we then remove the lowest and the highest and then average the remaining four. We do this to see if they are consistent with hitting the sweet spot in different locations. Some kids at the start of the clinics we hold will have a high of 62 but then a 33 and a 46. So we work on consistency as well.