Order of multiplication in $\prod_{i=1}^n$ notation

Question

Consider the expression $\prod_{i=1}^n O_i$ in a setting where multiplication is not commutative. Is there a convention as to whether to interpret this as $O_1\cdot O_2\cdots O_n$ or $O_n\cdot O_{n-1}\cdots O_1$?

One can certainly specify this in the preamble of an article, but I am wondering if there is an established convention.

Thanks