Hollis 500SE Second Stage Only (W/out Hose) Hollis Sale! from $ 429.95 USD /per Produc variants Default Title - Sold Out Qty. Sold Out Couldn't load pickup availability Refresh Old School. New Tech. The new 500SE utilizes a servo controlled valve to provide precision airflow and unparalleled performance for both air and trimix divers in a side exhaust configuration. *Miflex Hose shown is sold separately.