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For every natural number n we introduce a new weak choice principle $\mathrm {nRC_{fin}}$:
Given any infinite set x, there is an infinite subset$y\subseteq x$and a selection function f that chooses an n-element subset from every finite$z\subseteq y$containing at least n elements.
By constructing new permutation models built on a set of atoms obtained as Fraïssé limits, we will study the relation of $\mathrm {nRC_{fin}}$ to the weak choice principles $\mathrm {RC_m}$ (that has already been studied in [3] and [6]):
Given any infinite set x, there is an infinite subset$y\subseteq x$with a choice function f on the family of all m-element subsets of y.
Moreover, we prove a stronger analogue of the results in [6] when we study the relation between $\mathrm {nRC_{fin}}$ and $\mathrm {kC_{fin}^-}$ which is defined by
Given any infinite family$\mathcal {F}$of finite sets of cardinality greater than k, there is an infinite subfamily$\mathcal {A}\subseteq \mathcal {F}$with a selection function f that chooses a k-element subset from each$A\in \mathcal {A}$.