According to the TSA (Transportation Security Administration of the USA), which have the the strictest air travel security rules in the world, SAFETY RAZORS ARE PERMITTED in carry on, so the items in the HIS & HERs Travel Kits are fine for carry-on. I have carried my own safety razor (Gillette Mach 3) in my hand luggage a dozen times to Singapore, HK, Chiang Mai and PHUKET without incident.