This part is a kind of semiconductor called CP1005.

Function of this product has Multilayer Chip Couplers.

Manufacturers : Advanced Ceramic X

Image and pinout :

Some of the text within the PDF file :

CP1005 Series (Preliminary) Multilayer Chip Couplers Features  Monolithic SMD with ultra-small, low-profiled, and light-weight type. ACX Advanced Ceramic X Applications 0.4 ~ 6 GHz wireless communication systems, including DECT/PACS/PHS/GSM/DCS phones, WLAN card, Bluetooth modules, etc. Specifications Insertion Loss (MHz) (dB) VSWR Frequency Part Number Coupling (dB) Isolation (dB) CP1005-19C0897_ Q’ty/Reel (pcs) Operating Temperature Range Storage Temperature Range Storage Period Power Capacity 880 ~ 915 0.25 max. 1.3 max. 18.5  1.0 33.0 : 10000 : -40 ~ +85 oC o : +5 ~ +35 C, Humidity 45~75%RH : 12 months max. : 3W max. Part Number CP   Type  Coupling  Central Frequency  Soldering 1005  CP : Coupler 19 : 18.5 dB 0897 : 897MHz =lead-containing /L [ ... ]

CP1005 PDF Datasheet Download