RFM69W - 433mhz
This is the lower power (13dBm) version of the RFM69W transceiver used on the Moteinos (R1-R5).
These are no longer pin compatible compatible with current Moteinos (current Moteinos use the smaller format HCW variant), but are still popular and can be used to communicate with any RFM69 equiped Moteino similar board.
Also see the RFM69 library on Github for a RFM69 library that can be used with this transceiver.
RF Transceiver/Chipset Datasheet
HopeRF's copy cat datasheet: http://www.hoperf.com/upload/rf/RFM69HW-V1.3.pdf
Semtech SX1231h (RF chip apparently used on the RFM69) original datasheet: http://www.semtech.com/images/datasheet/sx1231h.pdf