The hole in the center in each bit causes it to be tamper resistance. Tamper Resistant sizes are: T-7, T-8, T-9, T-10, T-15, T-20, T-25, T-27, T-30, T-35, T-40, with Storage Sleeve Orange Case. Made of high-quality S2 steel, with sturdy hardened & tempered construction, Perfectly matched to most standard tamper-resistant German-made star 6-point screws.
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