Installed the 40mm on 25mm internal width rims and performed very well after riding known route with loose rocky picthes, hooks up well, rolls well on initial ride with 50% gravel 50% pavement. Installation was trouble free and with low volume bike compressor the seated first try.
Previous tires were 38mm light tread front and 35 file tread rear. Bonus reflective logo is MUCH appreciated since this bike doubles as a commuter.