Appears to be Master, but not top quality
Your review: Based on the packaging I believe they really are Master locks. But they appear to be seconds or culls since the cases have dings and dents and are unfinished at the shackle -- rough cuts in the sheet metal where the shackle moves. I cleaned up several with a hand file and removed burrs. Keys are white metal (plated) but the lock cylinder is brass, not plated as shown in the photo here. All the locks work fine, but only one had a large enough clearance for a fuel storage tank lock.