Accelerate sealing and save effort. Thicker 20 mm diameter design enables faster flow rate. Features a double stop valve oil pump—pumping takes only 5 seconds. Double-check valve design ensures faster flow rate and reliable two-way check valve operation for quick oil output. Enhanced oil-resistant rubber bulb absorbs more liquid; fine-grain surface design provides anti-slip and anti-aging properties. Thickened PVC tubing ensures long service life. Compatible with various vehicle types, including trucks, cars, and motorcycles. Instructions for Use: To use the suction pump correctly, insert a tube into the liquid to be transferred. Squeeze the rubber bulb firmly to expel air, then immediately block the tube outlet with your thumb. Release the bulb—the bulb will slowly expand and recover. Once liquid fills the bulb, remove your thumb from the outlet. Repeat 1–2 times to establish continuous siphon flow. This pump operates on air pressure to achieve siphon action. Due to the small inner diameter of the tube, flow rate is relatively slow. For optimal performance, position the rubber bulb as low as possible during use. Specifications: Commonly used as a hand pump on boats for fuel supply to outboard engines. Fast and easy handling. Operates on vacuum principle. Suitable for transferring gasoline, diesel, oil, water, and similar liquids. Materials: PVC, rubber, copper. Includes: 1 x pump, 2 x tubes. Tube length options: 1.5 m or 2 m. Tube diameter: 16 mm inner diameter, 20 mm outer diameter. Package includes: 1 x oil transfer pump kit.