[frankbmd]

The big ones are 13 inches x 10 inches x 3/4 inch.

My tin snips were to small to crack a corner.

A large locking pipe wrench would be ideal, but I didn't have one.

The pipe wrench is angled, so when gripping the slab at the flip end, the angle of the grips is not in the plane of the slab.

Then place the tightly gripped slab on the concrete garage floor so that the grips and the opposite edge of the slab as in contact with the floor. If you cannot bend over to perform this step a locking wrench will be necessary.

Take a deep breath and then step on the raised corner where the pipe wrench is gripping the slab.

Once you hear a loud cracking sound, release the pressure with you foot.

In my case the flip fell out immediately. The tin snips or whatever you for smaller slabs can then be used to crack the front and back of the case near the top. This step is best performed in a garbage can as the plastic fragments and can fly in all directions. With the top of the slab pointing downward, no fragments flew up out of the trash can. Continue to the opposite side and then the mylar sleeve and the card or whatever should slide out easily without damage.

A long screwdriver to pry open the slab once the corner is fractured might work, but I think with the large holder that the risk of damage to the contents might be higher with the inability to control lengthy cracking over the surface of the card or whatever.

If I had another slab to crack, I would make a youtube video, but alas I do not.

Happy Cracking