According to our supplier unfortunately they do not have the correct adapter.
In our range we have an adapter from 3.5 mm to 2.5 mm that should work, but we cannot guarantee it will work with that headset as we have not tested it.
InLine 2.5mm – 3.5mm (3m, Entry, 2.5mm)
What is "big head"? Dimensions needed.
If you fear it won't fit, why not use a 'Jabra Elite 65t' which has no headset.
Otherwise, the Evolve 40 is great!