(Mishnah): One who had Ma'aser Sheni money in Yerushalayim and he needs to use them to buy inedible Chulin; if his friend has Chulin produce - he should say to his friend, "Let the Kedushah on that money be redeemed onto your produce''. Consequently, the friend must now eat his produce in Taharah (as Ma'aser Sheni) and the first person can now use his money as he wishes. This technique should not be told to an Am HaAretz unless it's Ma'aser Sheni of Demai.

If he has Chulin produce in Yerushalayim and Ma'aser Sheni money outside, he can say, "Let the Kedushah of this money be redeemed onto that produce''.

If he has Ma'aser Sheni money in Yerushalayim and produce outside, he can say, "Let the Kedushah of this money be redeemed onto that produce'', as long as he then takes the produce and eats it in Yerushalayim.

Money may be taken into Yerushalayim and then removed. Produce may not be removed once it has been brought in.

(Rabban Shimon ben Gamliel): Even produce may be removed. (This will be qualified in the Gemara.)

If produce was completed (thereby making it Tevel) and it was taken through Yerushalayim, its Ma'aser Sheni must be returned and eaten in Yerushalayim (even though it had not yet been separated when it passed through).

And if they were brought in when they were not yet complete, for example, baskets of grapes to be used for pressing or figs for drying...

Beis Shammai says that its Ma'aser Sheni must be taken and eaten in Yerushalayim. Beis Hillel says that he may redeem it and it can be eaten anywhere (as the Ma'aser Sheni is not considered to have been brought into Yerushalayim).

(R. Shimon ben Yehuda citing R. Yosi): Beis Shammai and Beis Hillel agree that if the produce wasn't yet completed, the Ma'aser Sheni may be redeemed and eaten anywhere.

They disagree over produce that was already complete - Beis Shammai say that he must return the Ma'aser Sheni to Yerushalayim and eat it there. Beis Hillel say that he may redeem it and eat it anywhere.

Tevel of Demai may be taken in and out and then redeemed outside Yerushalayim.

(Gemara): (The Mishnah taught) 'This technique should not be told to an Am HaAretz unless it's Ma'aser Sheni of Demai.' But if it is certain Ma'aser Sheni, it should not be told to him, as one may not give certain Ma'aser Sheni to an Am HaAretz (as he will not be careful to prevent it becoming Tamei).

(Rabban Shimon ben Gamliel disagreed with the Chachamim in the Mishnah, saying that even produce may be removed.) He was referring to removing it in order to make dough. It must then be immediately returned. (He says that the prohibition to remove it is Rabbinic and they were lenient to allow him to remove it if, for example, the millstones that he requires are outside Yerushalayim.) (Note: This follows the explanation of Rav Chaim Kanievski shlita.)