Quick Answer: Spank tests all our stems to meet and exceed all industry safety standards, (CEN/ISO), as they are factory assembled. Spank uses only high grade hardware in our stem assemblies. It is not recommended to substitute stem bolts with a different material or specification, regardless of fit. Attempts to modify your stem with alternate hardware will void your warranty, and could lead to premature failure. If you need to replace stem bolts, please contact your regional Spank distributor, or sales and service center, or email your inquiry to support@spank-ind.com