Preheat oven to 375°F.

Combine 1 1/2 cups flour, oats, brown sugar and salt.

Add butter, mixing until crumbly; reserve 3/4 cup mixture for topping.

Press remaining mixture onto bottom of greased 13 X 9 inch baking pan.

Bake for 10 minutes.

Sprinkle chocolate and nuts over partially baked oat base.

Combine caramel topping and remaining 1/4 cup flour; drizxle over chocolate and nuts.

Sprinkle reserved crumb mixture over caramel mixture.

Continue baking for 20 minutes.

Cool thoroughly; chill to set chocolate.

Cut into bars.