Xtreme Design 5A Nylon Tip Drumsticks. The new Xtreme Design Series models, XD-5A, XD-5B and XD-Rock, have been designed and manufactured to meet the great demand of drummers who have been asking for stick models in between the very popular Vater Power 5A/Power 5B models and the Rock model.The results are three extremely well balanced, weighted and responsive models that are available with a rounded barrel-style wood tip with nylon tip versions to match.