We have put together a spark plug kit which includes everything you need to change and gap the spark plugs for your N54, N55, B48 or B58 BMW.
The kit includes:
Spark plug gapping tool
BMW thin wall spark plug socket
Feeler gauge set
6 x spark plugs
Spark plug choice is:
NGK 97506 SILZKBR8D8S
NGK 94201 SILZKGR8B8S
BMW 12122455258 (Supra/Z4/B58TU style plug)
M140i
M240i
M135i
M235i