In the soldering process, fluxes or pastes are often used, which are sold in syringes. It is a convenient packaging as it facilitates accurate dosing. But sometimes it is difficult to accurately dose by quantity, especially with thick flux-based solder pastes. In professional applications, pneumatic automatic dispensers are used to dispense the right amount from the syringe. But such devices are expensive, so it is not profitable to use them by hobbyists or small businesses. And it is for such non-professional applications that I recommend the manual dispenser.