It is called a "security Torx" bit. I think it is a T-15 size but not sure on that one. Most auto supply places will carry something like that. Got mine at Checker Auto but I had to buy a kit of bits with like T-2 to T-25 sizes. Paid like $8 but now I got em all (I guess I can now remove the doors on public bathroom stalls if I wanted eh? )