GS500, GS500Z, GS501, GS501Z, Duplex Control Systems. Spaform Esperanto range, Serenity Spas and more.. LCD, basic 3 digit style. Castle Hot Tubs is a well established, trusted name in the water care industry, we will do our very best to ensure that your purchasing experience with us is a pleasant one.Goods ordered before 1pm will be sent out on the same day. This item is in the category "Garden & Patio\Swimming Pools, Saunas & Hot Tubs\Hot Tubs". The seller is "castlehottubs" and is located in this country: GB. This item can be shipped to United Kingdom.