Minoura Japan – AHD-1

When you park your bike outside, helmet is usually an impeditive item. It's bulky to hold, it should be stolen if just hooking on bike, and it's hard to imagine not to wear helmet for your safety.
How about wiring the helmet together with the bike with long cable?

AHD-1 is constructed with U-shape metal hook and metal plate. Put the hook into the slit from inside and put the cable into the hook, then nobody can steal it.
AHD-1 is made of metal but it's lightweight enough and won't bulky in your saddle bag.