The Innova Mini Marker Regular looks like a stock stamp disc. It's purpose is to be used to mark your lie so you can throw your disc from the same spot. These meet the legal requirements set forth by the Professional Disc Golf Association.
They're a stiff plastic and pretty durable. You can throw them and they won't break when they hit a tree. These mini discs are great for kids to throw if they're not quite ready for a full on disc.
You never have enough minis. Make sure you've got one in your car, one in your bag, and a couple for the friends who forgot theirs. These Innova Mini's are always needed out on the course.
Snag some of these discs today and practice playing from your legal lie today!