How many times you can use catapult turtle effect yugioh?

You can only use the effect of "Catapult Turtle" once per turn.

This is because its effect states: "Once per turn, during your Main Phase: You can send 1 monster from your hand to the Graveyard; Special Summon this card from your hand."

This clearly indicates that you can only use the effect once per turn, even if you have multiple "Catapult Turtles" in your hand.