We use only the highest quality brass spokenipples when building your custom wheelset.Brass nipples are the strongest and longest lasting spoke nipple option. They areslightly heavier than alloy spoke nipples,but we alwaysrecommend them over alloy nipples as they will be the most reliable.Why no alloy nipples? Alloy nipples simply are not durable enough for most mountain bike wheelsets, therefore we don’t offer them as an option.