The DNA Step Ladders are ladders of defined sizes with exact incremental steps between bands. The ladders are not intended for use in quantitative analysis. Each ladder is provided with a tube of 6X Blue/Orange Loading Dye. The fragments may be stained with ethidium bromide.

10bp DNA Step Ladder: Ten blunt-ended DNA fragments ranging from 10bp to 100bp in exactly 10bp increments. All of the bands are of approximately equal intensity with the exception of the 10bp band, which may appear slightly less intense.

25bp DNA Step Ladder: Twelve DNA fragments ranging from 25bp to 300bp in 25bp increments. An 1,800bp "backbone" fragment is also visible. The 300bp band is ≈3 times more intense than all other bands.

50bp DNA Step Ladder: Sixteen DNA fragments ranging from 50bp to 800bp in 50bp increments plus an 1,800bp "backbone" fragment. All bands except the 800bp band are of equal intensity; the 800bp band is ≈3 times more intense.

100bp DNA Step Ladder: Forty blunt-ended DNA fragments ranging from 100bp to 4,000bp in 100bp increments. Two internal features facilitate band identification. A high-intensity 500bp band stands out at the lowest segment of the ladder (<1kb). Bands within each segment (<1kb, <2kb, <4kb) have approximately the same intensity.

200bp DNA Step Ladder: Thirty-three blunt-ended DNA fragments ranging from 200bp to 6,600bp in 200bp increments. The 1,000bp band appears more intense than all other bands, which are of approximately equal intensity.

1kb DNA Step Ladder: Ten blunt-ended DNA fragments ranging from 1kb to 10kb in 1kb increments. All bands except the 5kb band are of equal intensity; the 5kb band is ≈3 times more intense.