Wiseco piston kit that came with a bunch of old dealer stock I purchased. Box is marked 361 PS and 73-74 KX250, but as this is old stock from a dealer and hadn't been touched in years, please look at the photos and do your research. Caliper reads approx 69.5mm. Piston looks unused, has minor handling marks that show in the photos, nothing major. Ring looks perfect. Please do your research before purchasing and I can take any additional measurements you might require to verify fitment. Thank you!