Plates are available in different thicknesses.
The emulsion thickness will give you the maximum
depth of your impression.

Steel-backed plates will give you a
slightly sharper result.

These are the plates I use myself most often

I prefer to use steel backed plates for nearly all of my work and only use the plastic ones for designs with less detail.

• Medium Plastic Based
  Base = 0.21mm (0.01") Emulsion = 0.93mm (0.04")
  This plate is thicker and is the most useful size to have, it works well for text & patterns and all general texture plate making. It can still be washed out to a shallow depth only and be used for Keum-boo. Cut with heavy duty household scissors.
  
  
• Medium Steel Based
  Base = 0.43mm (0.02") Emulsion = 1.07mm (0.04")
  This plate is similar in depth to the KB110 but is Steel backed. I use metal shears to cut these ones. The emulsion of this plate is a little different and makes a crisper image than the plastic backed plates do, making it especially suitable for lettering and images that must have very sharp detail.
  
• Thick Plastic Based
  Base = 0.25mm (0.01") Emulsion = 1.50mm (0.06")
  This is the thickest Plastic-backed plate I use, it makes a very deep impression, but it's a little harder to get PMC out of small details. This plate is very useful for Champlevé enamelling and lettering where a higher relief is required.
  Cut with heavy duty household scissors.
  
  * I also use a steelbacked variety in this thickness, it is a lot harder to cut than the thinner plates if you don't have a guillotine or bench shears.