Sahara Automatic Bilge Pump S1100 Series. Part # 4511-7. An automatic-switch bilge pump is a requirement for any vessels 20' and over with sleeping accommodations, but is a great convenience for any size boat. The Sahara has everything contained in one compact yet durable package pump, wire seals, strainer, and mercury-free switch and installs quickly and easily in tight spaces. Pumps include 36 lengths of 16-gauge caulked and tinned copper wire. S1100 is Attwood's most powerful and efficient automatic pump. High capacity for larger boats and yachts. 1100 GPH at open flow, 973 GPH* at 3.3' head. 1-1/8 hose outlet. Features 12V. Hose Size 1-1/8 I.D. 36 Wire. 3-Year Warranty Part # 4511-7. An automatic-switch bilge pump is a requirement for any vessels 20' and over with sl 12V. Hose Size 1-1/8 I.D.