Does this box need to be bolted down or does it just sit in place?

It mounts at factory points behind the rear seats — no drilling or permanent fasteners required. Test-fit it first to confirm clearance with your seat adjustment range.

Will this block rear seat legroom?

It's designed to fit the rear seat area without eating into passenger space, but how much it impacts comfort depends on seat position. Measure your rear seat depth before ordering to be sure.

Can I lock it?

The box assembly is solid, but locking hardware is not included — you'll need to source aftermarket latches or locks separately depending on your security needs.