PHILADELPHIA -- Phillies catcher Cameron Rupp squatted behind home plate Friday night with a new piece of equipment.

He had a wristband on his left arm, much like NFL quarterbacks wear. But instead of play calls, this one had the strengths and weaknesses of every Reds batter. It is something other catchers use, most notably Dodgers catcher Yasmani Grandal and retired Cubs catcher David Ross , but it is the first time the Phillies have tried it. Andrew Knapp wore the wristband for the first time Sunday.

"It's a refresher," Rupp said. "It's where to go with certain guys. If you get stuck, if a guy has fouled off a few pitches, it's where to go, it's what your options are. It tells you how aggressive certain guys are. There is more than one way to get certain hitters out, so if you got him out a couple ways and you get into a big situation in the game, you look at the sheet and say, 'Hey, we can go there.' If the guy hits his spot it's an out."

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The Phillies talked about using a wristband last year, but it took until this weekend's series to implement it. But before Rupp wore it, the Phillies had to figure out what to put on it. They wanted to put enough information on the wristband to be helpful, but not cram too much information on it that it becomes impossible to use.

The wristband has hot and cold zones for hitters. It tells catchers how to pitch hitters with two strikes. It tells them a hitter's swing percentage in certain situations.

It is color coded to make it easy to reference. Phillies manager Pete Mackanin said red means no and green means yes.

"If a guy has an 80 percent swing percentage at 3-2, then you don't necessarily have to throw a good strike," Mackanin said. "They'll chase."

Rupp said he glanced at the sheet a few times during Friday's game. Of course, being a new piece of equipment, he also forgot to put it on before one inning.

"I don't think it's a knock on anybody," Rupp said. "It's just a little refresher. A lot of it is based on the pitcher out there, too. It's what he can and can't do, so you've got to steer him away from putting himself in a hole."

Todd Zolecki has covered the Phillies since 2003, and for MLB.com since 2009. Follow him on Twitter and Facebook and listen to his podcast.