$\displaystyle \prod_{i \in \mathbb{N}} \mathbb{Z}_2 \cong \prod_{i \in 2\mathbb{N}} \mathbb{Z}_2 \cong \prod_{i \in \mathbb{N}} \mathbb{Z}_2 / \prod_{i \in 2\mathbb{N}+1} \mathbb{Z}_2$