First of all, I have to admit that I have not tested any of these fuses for their breaking performance. However all their ratings are clearly marked on the metal end cap of each fuse, the plastic box organizes them very well with a label clearly identifying them. Black nylon screw cap fuse holders hold fuses very tightly. The plastic box is also in a corrugated cardboard box, so it arrived safely. The fuse holder rating is only 10 amps (AWG16 wire) but I'm fine with that.