I got this pad holder when Gizmo started eating his pads
Amazon.com: Rascal Dog Litter Box PIDDLE PAD... , it works amazing,and their spray is awesome too. Gizmo immediately stopped tearing tem up once i got this type. They also have the artificial turf for it as it has a reservoir in the bottom of the holder, but I just use it with pads, because its easier to clean. I took off the sides for now, but if he starts lifting his leg as he gets older i will put them back on lol, they are really easy to snap into place.
Gizmo is also trained to go while our for walks as well though :-)