Sharkstooth scrim is what almost all theatrical scrims are constructed of. One of the most popular scrim effects is the reveal (also known as a bleed-through). When lit properly from the front this material has an opaque look. Once you remove the front light and light it from the back it will reveal what is hidden behind.
A great effect for transitioning from the outside to the inside of a building without the moving of scenery or a break in the action. Sometimes referred to as Sharks Tooth Scrim.