This listing is for 2 carbon rods, 10mm diameter and 305mm length. 
Electrical conductivity is typically less than 1 ohm from end to end. Excellent for electrochemical experiments, etc. 
As use as an anode in electrochemistry, ideally maintain current density below 40 mA/cm2 or 125 mA per cm length (30.5 cm total length) for maximum longevity.