MorTime 3 AA To 1 D Converter - Parallel AA to D Battery Adapters Holder 1.5V Output Case,Pack of 4 (4 pcs) To connect three AA batteries together for replacing a large D battery. Size  5.8 x 3.3cm / 2.28 x 1.3 inch Material: Plastic, Metal Type: 3 AA in Parallel Output voltage: 1.5V