You can purchase breathalyzer for driving in France fron Value Breathalysers
The latest news on the french breathalyzer law is that, as was speculated , it has been now been confirmed that the new french law that requires motorists to carry NF approved breathalyzer kits in their cars from the 1st July 2012 or face fines will not actually be enforced by police until 1st November 2012.
This is good news for motorists travelling to France this summer and for manufacturers of the single use 0.05% breathalyzer kits who have struggled to keep up with sudden demand for the 0.05% BAC breathalyzer kits.
You can buy breathalyzer kits for France with NF certificate from Value Breathalysers for the new french breathalyzer law
http://www.value-breathalysers.co.uk/acatalog/SINGLE_USE_BREATHALYSERS.html