Help ! what is this part ? SPDT or LNA

Hi,
In my one radio , I found this part , the mark is 259 and 912. Anyone known this part? it looks like a spdt but I can not find out the spec in google.
the size is smaller than sot26. 6SMM?

Thanks.

Is it PE4259?
http://www.psemi.com/pdf/datasheets/pe4259ds.pdf
I found it with "sot-363" key word.