Promo code RobertsHawaii

Does anyone have reference code for RobertsHawaii? Apparently its on their brochure. Want to see if it lowers the cost when booking online.

We have booked special combo tours with Roberts. They offer 3 or 4 tour specials for people who are booked on the various cruise lines for each of the islands. The prices are great if you do it this way. Just check their website.