Since finding out that Helvetia supplied watches to G & M Lane for their Aero and Aeroplane range of watches I have been on the lookout for other companies using Helvetia watches branded as their own.
The latest is Abercrombie & Fitch for their 'Shipmate Watch' in the early 1930s. At this time Abercrombie & Fitch were a sporting goods and outdoors store. These were the same watches that G & M Lane used. It's interesting that G & M Lane branded them as pilots' watches and Abercrombie & Fitch as sailors'. (See here for more details.)
I think they were popular for resellers as they were some of the few shock protected and waterproof watches available at the time and they were also available with centre seconds.
If anyone else finds any more of these watches branded with any other company I'd be interested to know. Please contact me via the contact page.