The Supercoiled DNA Ladder contains fragments from 2 kb to 10 kb at 1-kb increments and an additional band at 12 kb. Each supercoiled band is at a known concentration, with the 7-kb band at a higher concentration than the others. The resulting brighter band in the middle of the ladder acts as a useful reference point.
Accurate size determination facilitated by evenly spaced bands
Fragments are exact multiples of 1000 bp
Includes useful reference point for determining location