This part is a kind of semiconductor called 2450BM15A0015.

Function of this product has 2.45GHz Impedance Matched Balun-Filter.

Manufacturers : Johanson Technology

Image and pinout :

Some of the text within the PDF file :

"High Frequency Ceramic Solutions" 2.45GHz Impedance Matched Balun-Filter for Atmel Chipset AT86RF232 and AT86RF233. Platforms: ATMega256RFR2, Zigbit 256RFR2, Zigbit RF233, ZigBit RF233+FEM, Extension RF233, USB RF233 P/N 2450BM15A0015 Page 1 of 3 Detail Specification: 1/21/2013 General Specifications Part Number Frequency (MHz) Unbalanced Impedance Differential Balanced Impedance Insertion Loss (-40C to +85C) Insertion Loss (-40C to +125C) Return Loss Phase Difference Amplitude Difference Power Capacity Differential Mode Attenuation Common Mode Rejection 2450BM15A0015 2400~2500 50 Ω Impedance match to: Atmel AT86RF232, AT86RF233, ATMega256RFR2, Zigbit 256RFR2, Zigbit RF233, ZigBit RF233+FEM, Extension RF233, USB RF233 1.1dB Typ, 1.5 dB max. 1.3dB Typ, 1.9 dB max. 9.5 min. 180 ± 10 [ ... ]

2450BM15A0015 PDF Datasheet Download