Unfortunately, the image provided does not help to identify the part number.
XSON-3 was used is our transistors, we would like to inform you that NXP has divested it´s Standard Products business on Feb 6th 2017, his new standalone company is called “Nexperia”
We would like to ask you to re-enter your inquiry at the Nexperia support web page: www.nexperia.com/support.
FYI in this link you will find our current XSON-3 part numbers ( be aware none of them match with the image):
https://www.nxp.com/packages/SOT1122-1
Best regards,
Alondra