HTMS Phutthayotfa Chulalok (FFG 461) (Thai: พุทธยอดฟ้าจุฬาโลก) is the former USS Truett (FF-1095), Knox-class frigate. The ship is named after the first king of the Chakri Dynasty, King Phutthayotfa Chulaok the Great. The Royal Thai Navy first leased the ship from the US Navy after she was decommissioned on July 30, 1994. The ship was eventually purchased on December 9, 1999. A Phutthayotfa Chulalok-class frigate, she has a sister ship, the HTMS Phutthaloetla Naphalai (FFG 462).