The Kuretake ZIG 2 Way Glue pens are blue when wet and clear when dry. For a permanent hold, apply glue to one paper surface and adhere it to another paper surface. For a repositionable hold, apply it to a paper surface and allow it to dry clear before adhering it to the other paper. The 2 Way Glue Pen glue is both Acid free and Xylene free.
The Chisel Tip is 4mm.