as many times as needed
There is no rule in MLB that specifies how many times a catcher may visit the pitcher during a game.
There are 9 defensive baseball players on the field at all times here is a list: Pitcher, Catcher, Firstbase, Second Base, Third Base, Shortstop, Left Field, Right Field, Centerfield.
You can get baseball equipment in russia but not many stores there for it. Russia doesnt play baseball really only lapsha which is criket here in U.S.
as many times as you want
According to my Kindle, the word "goddam" appears 244 times. According to ChaCha, it appears 255 times.
My catcher gear last year was Under Armour. Under Armour is the best catcher gear money can buy. All the other brands doesn't protect the chest as well. The Under Armour chest piece is broader on the shoulders and has more padding. I suggest the Under Armour catcher gear.
There are nine fielders on the field at one time including pitcher and catcher.
Baseball Players don't need a ton of equipment unless they are very serious players. I have made a list below of what is needed. Don't be conned into buying very expensive equipment if the ball player isn't going to be a very serious player or is going to grow out of the equipment soon.-Glove-Bat-Batting Gloves-Cleats-Baseball Pants-SocksThere are many other things they might need if they are a serious player but for the recreational player they are optional.
9 players are on the field at all times. Catcher, First Base, Second Base, Short Stop, Third Base, Pitcher, Left Outfield, Center Outfield, Right Outfield.
Softball uses the same fielding as baseball, assuming you're talking about high school level and up. Pitcher, catcher, one player at each base plus a shortstop. Three in the outfield for a total of 9.