We use those Gymnastic type Mats in the Gym. Players are required to wear Socks and Sweat Pants and not the
Jogging or Warm-up type Pants
I have seen these actually melt those fabric's made of Nylon or Polyester during sliding practice.
Also remember to coat the Mats with Talc Powder, Baby Powder works
just as good ( Will need at least a couple Bottles) and this helps when the players are in the Figure 4 Slide, you will need to coat the Mats with Powder every so often as it will be wiped off after a few players slide.
We also use those large Dust Mop that the janitors use to clean up the Powder afterwards. Kinda messy but the players enjoy it, and the parents chip in to help with with the clean-up. This would work just as well outside with out the clean-up or in a garage, don't believe I would recommend it for inside a house. It's a Great thing to do on cold or rainy days.
Figure-4 Sliding Only!
Caution! The Gym Floor will becoming slippery when the Powder is applied to the mats and the players track it on the floor.
When it's hot in the Summer, I use a Slip & Slide for Sliding Practice the Team has a Blast! Remember to tell them to bring a change of clothes and a towel.
HAVE FUN!
FASTPITCH! Anything else, And you're playing to SLOW!