I ordered a 3-watt laser & interlock.
I ordered a 3-watt laser, which shipped to me here in the United States from the United States address. But all lasers need to be sold with their safety interlocks. The laser alone without the interlock, does not function. So of course I ordered the interlock at the same time in the same order, but they didn't have any interlocks in the United States. So I had to wait until the delivery from China arrives to use the laser. Not great. The interlock should be included with the laser, even if the bundle price is more. More importantly, they should be shipped together. Edit: As of now, they have interlocks w 10M cables in the USA. Be careful to select USA if that's where you are.