Namek Dragon Ball
From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
The Namek Dragon Balls were created by the Grand Elder of Planet Namek. Each Namek Dragon Ball was in the custody of one of seven Elders. If someone wanted a Dragon Ball, each Elder had to engage in a contest of wits, a contest of strength, and to ask the reason for the person's wish. You would then be judged if you were a man of valor by the Elder.
These Dragon Balls were similar to the Earth Dragon Balls in power and appearance, however, the Planet Namek set are were as large as volleyballs. Two extra precautions had to be taken with the Namek Dragon Balls. First, the summoner was required to utter a Namekian password in order to summon the Dragon God, Polunga. Second, the wish had to be spoken in Namekian. Once Polunga was summoned, he had the ability to grant three wishes that were somewhat less powerful than Shen Long's wishes. For example, Polunga could only revive one person at a time while Shen Long could revive an infinite number of people at a time (although he was eventually modified to do mass revivals after the Freeza Saga). Polunga could grant the same wish as many times as the summoner pleased. The time the Namek Dragon Balls took to restore was 130 days, not the 365 days required for the Earth Dragon Balls, as a year for Planet Namek lasted only 130 Earth days.