Dolba BD11 dipole (sleeve) Flarm antenna, so called 'Sperrtopfantenne'.
The best dipole antenna on the market together with the BD12.
For installation inside the fuselage (GFK only).
With BNC female connector.

Frequency: 868 MHz
Impedance: 50 Ohms
Weight: 65g

Dimensions:
L=220mm (excl. BNC-connector)
D=20mm