Tyvek Himber Envelopes are great utility poker card size, double sided himber envelopes, brown color, made in very durable tyvek material.

They are made for switching and multiple outs:Switch any freely chosen card into your force cardUse any two force cards and reveal either one as your predictionUse two double face cards in one envelope to have four possible outcomesUse any blank card with any words, symbols and numbers for the above applicationsI use two of them in my magnetic Himber wallet and there are four outs but spectator sees one envelope and one card.

Comes with 10 tyvek envelopes. No instructions included.