The pump output section has a bent screw, removable. inside there is a white cross rose, can adjust the amount of oil. This machine is quiet when used. Features: Has a removable bent screw. A cross rose can adjust the amount of oil. Extremely quiet when used. Main scope of application is smoke machine. 30DCB and 40DCB optional for you to choose. Made of high quality materials, durable and compact. Specifications: Main material: stainless steel Type: 40DCB; 30DCB(optional) Voltage: 110V-120V Light source power: 18 (W) Protection class: IP40 30DCB: Item weight: 115g / 4.06oz Package weight: 125g / 4.41oz 40DCB: Item weight: 130g / 4.59oz Package weight: 140g / 4.94oz Item size: about 10 * 3 * 2cm / 3.94 * 1.18 * 0.79in Package size: 15 * 4 * 2cm / 5.91 * 1.57 * 0.79in Note: 30DCB suits for 400W smoke machines only. 40DCB suits for 900W smoke machines only. The color of the is delivered at random. Package list: 1 * Smoke machine oil pump