If you're asking about the mounting hardware for the Eos vs the Eos Bike, they are different.
Correct, the back half of the housing is different on these lights. The headlamp version is meant to be attached to a 1" strap or webbing. The bike version has a system that allows one to switch between handlebar and webbing brackets.
A possible solution: remove the head strap (there are slots in the bracket to allow this) and use a 1" velcro strap to attach to helmet. Hope this helps.
-PTEC
I wanted to mount to the handlebar though, any suggestions?
Thanks!
Get a 2xAA flashlight and a Twofish or similar handlebar block. Brighter and longer running than an Eos. And will be more stable on your bars than whatever rig you make for your Eos.