Replacement O-rings for the WP-FXF500 (F300/ F500/ F550/ F600/ F660EXR) underwater housing. It is recommended that the O-ring is replaced at least once a year. Contains 1 x white O-ring, 1 x orange O-ring and remover tool. Only use Fujifilm Silicone Grease with the O-ring. It is important to follow the instructions in the waterproof housing manual when replacing and caring for O-rings.