Maritime / Nautical Navigation Instruments, Vintage Diving Helmets & Home Décor Our replicas of antique nautical navigation instruments such as compasses, sundials, and sextants make perfect gifts for maritime enthusiasts. Or, if you're looking for something even more rare and unique, our deep sea diving helmets are just the thing. Ideal gift ideas for boat lovers, diving enthusiasts, and anyone who has ever felt the pull of that horizon.