The product of the unbalanced reaction between aluminum (Al) and bromine gas (Br₂) is aluminum bromide (AlBr₃).

Here's the unbalanced equation:

Al(s) + Br₂(g) → AlBr₃(s)

To balance this equation, you'll need to adjust the coefficients in front of each chemical formula. Here's the balanced equation:

2 Al(s) + 3 Br₂(g) → 2 AlBr₃(s)