3M Primer 94 increases the bond strength of acrylic and rubber based adhesive tapes Repackaged under 3M contract in a convenient reusable marker / pen with reversible tip and two flow widths of .100"/2.54mm (round tip) and .200"/5.08mm (chisel tip) Contains .47fl oz/14mL of 3M Primer 94 which is equivalent to 21 Primer 94 Ampule Pens at .022fl oz/0.66mL each