8mm Shaft 406mm=15.984 Hardened Rod Linear Motion

Checked with calipers and fairly accurate we'll see how accurate they are once assembled. Had to cut them for my application and the metal is very hard. Tried a band saw ? no go tried my lathe ? broke a carbide tip ended up using lathe and dremel with cut off wheel. I'd say they're made of some da** hard metal and should last a good long time.

They work just fine but I they had some discoloration and surface roughness. I thought about returning them but decided to give them a try and they seem to be working fine. I suspect these may have been 'marginal' rejects from a manufacturer.

I will use this rods in a 3D printer very good quality and finish

Although I know next-to-nothing about metal alloys these work well for robots. At retail price they should be individually wrapped when shipped but they arrive shiny straight new and meet specs.