Do you want your platemaker to process both steel-backed and plastic-backed letterpress printing plates? Then use this mounting rubber. Platemakers that use a magnetic sheet to hold plates during washout can’t process plastic-backed plates. Our magnetic mounting rubber can temporarily attach on top of the platemaker’s magnetic panel and allow you to process both plastic and steel-backed plates. Simply attach our magnetic mounting rubber to the platemaker’s magnetic platen. Both plastic-backed and steel-backed polymer plates stick equally well to our mounting rubber. You may have to adjust brushes down to accommodate the extra thickness of the magnetic mounting rubber. This product is ideal for borrowed or community platemakers where permanent modification—adhering mounting rubber permanently to the platen– isn’t possible. The 9 x 12 size fits an A4 platemaker. The 12 x 18 size fits an A3 platemaker. Between plates, dry the mounting rubber with a squeegee, or else the next plate will not stick to the mounting rubber.