Tx and RX or just Tx?

Is this antena, only for receiving or also for transmitting a wireless
signal? (signal extension)
Thanks
Vinnie

" 5.1-5.9GHz 21dBi directional panel antenna:

Newly designed 5.1~5.9GHz 21dBi directional panel antenna for both
5.25~5.35 and 5.8~5.9GHz band.

Brand new from manufacturer. Works very will for all 5GHz 802.11a
radios including WiFi, Breezecom, Alvarion, Cisco, Orinoco, Linksys and
Dlink etc.

***See specs sheet below for details***

Technical Specifications


REMARKS
1 Frequency Range 5100 - 5900 MHz
2 Impedance 50 W
3 VSWR (or Return Loss) < 1.5:1 ( or > 14dB)
4 Gain >21dBi
5 Polarization Vertical, Linear
6 3dB Horizontal Beamwidth 12 Degrees
7 3dB Vertical Beamwidth 16 Degrees
8 Front to Back Ratio >35dB
9 Max. Power Input 20W
10 Connector N Female, Bottom Feed Or Custom Design
11 Appearance Panel Type
12 Size 8 x 11.5 x 1 [inch]
13 Housing Material Powder Coated Aluminum
14 Radom Material ABS with UV Protection
15 Radom Color White
16 Case Design Water Resistance
17 Weight 2.5 Lb
18 Wind Loading (Frontal) > 10Kg 200km/h
19 Temperature Range -45 to +75 Degrees
20 Storage Temperature -30 to +75 Degrees
21 Lighting Protection Direct Grounding
22 Mounting Hardware Clamp Set
23 Life Expectancy 20 years "