Check the listing for details. Alerts Combo Pack, 2 Monitors,2 Count (Pack of 1). Color: Multi-colored, Condition: New. Listed at 23.99 USD. Alerts Combo Pack, 2 Monitors,2 Count (Pack of 1) Description: Miscellaneous aquarium ammonia Alert continuously monitors and detects free ammonia in marine or freshwater aquaria. Ph. Alert is a unique color device designed to be placed in the aquarium or filter and moall items are brand new, never worn and never used.. Features: This product is easy to use This product adds a great Value This product is Manufactured in United States Returns: In the unlikely event that you would like to return your purchase, we allow returns that are processed within 30 days of date of purchase. Please contact us for a return authorization and the return shipping address. Shipping costs are non-refundable. Payment: The following forms of payment are accepted: PayPal All major credit cards. Shipping: Our orders are generally handled and processed within 1-2 business days. Expedited shipping options are also available and can be selected during checkout. At this time, we only ship to physical addresses that are located within the 48 contiguous states of the United States of America. We are unable to ship to P.O. boxes, APO or FPO addresses, or international addresses directly. We are not responsible for undeliverable / incorrect addresses