This tiny external antenna is great if you need to mount your GPS Expander under carbon fiber, or in other "RF challenging" locations. 
 
The Expander will pick between the strongest of the two signals (from the built-in antenna or this External Antenna) which can improve reception if your model is upside down, etc. Includes cable with MMCX jack.
NOTE: if you have our older GPS module (not GPS-5HZ) please check to make sure it has the gold MMCX connector protruding from the red heat shrink.