mouse.TargetFilter not working?

I've created a wall and added it to the mouse.targetFilter, but the mouse is not ignoring the wall.

tool.Equipped:connect(function(eventMouse)

    eventMouse.Move:connect(function()

        eventMouse.TargetFilter = game.Workspace.Wall

        if (playerMouse.Hit ~= lastHit) then
            lastHit = playerMouse.Hit
            lastTarget = playerMouse.Target
            print(lastHit)
            print(lastHit)
        end
    end)
end)