If you're planning to seal dozens of invitations, then using the electric melting pot or the glue gun is the quickest, cleanest and most efficient method. Both of them are easy-to-use and no flame required.
The electric melting pot is a combination of being traditional and modern. You can enjoy the fun of wax sealing and have the efficiency at the same time. It works with both wax sticks and wax beads.
The glue gun is more for efficient. It works only with the glue gun wax seal sticks.
We also recommend using multiple stamps of the same engraving. Thus you can continue seal with a second stamp while the first one cools down.