Overview Product Description DSU 500A - 830V09831313 - 56 kbps DSU/CSU RS232 Interface External (Refurbished) 90 Day Warranty Product Videos Custom Field Product Reviews Write a Review Write a Review × Racal DSU 500A Rating * Select Rating 1 star (worst) 2 stars 3 stars (average) 4 stars 5 stars (best) Name Email * Review Subject * Comments *