S1077. inkmethis Envelope Ruler
Perfect for easily adding guide and slantlines to non-white paper. Ruler lets you choose from guides at 4mm and 5mm x-heights with 3:2:3 ratio, and 6.5mm x-height at 1:1:1 ratio. Complete with both 55- and 52-degree slants and center marks for A2, A6, A7, and A9 envelopes.
This worked great on a big envelope order. The client sent dark envelopes so I could not use my light pad.