Marginality is direct power-closed

Statement
Suppose $$H$$ is a marginal subgroup of a group $$G$$, and $$\alpha$$ is a finite or infinite cardinal. Then, in the direct power $$G^\alpha$$, $$H^\alpha$$ is a marginal subgroup. In fact, it is marginal for the same variety that $$H$$ is marginal in $$G$$.

Proof
The proof is straightforward.