Humpert is a component manufacturer mentioned at the Birdy Freunde site in Germany:
http://www.birdy-freunde.de/mybirdy/lenker.html

Under the X-ACT brand there's some nice looking folding handlebars; check out the FHS, AHS bars ... and the Hornbar Vario which is kinda like the Bike Friday H Bar and makes sense as it includes the bar end section.

http://www.humpert.com/de/bikeparts/...16&produkt=135

No weights indicated for any products unfortunately.