A MOSFET (Metal Oxide Semiconductor Field Effect Transistor) is a crucial electronic upgrade for gel blasters, serving as a switch to regulate the electrical circuit and enhance performance. By replacing the traditional mechanical trigger switch, a MOSFET transforms the trigger into an electronic signal provider, enabling precise gearbox operation. This integration, often referred to as adding an "electronic brain" or Electronic Trigger System, ensures smoother and more efficient functionality. Additionally, most MOSFETs feature Active Brake technology, which halts the motor immediately after the trigger is released, improving precision and eliminating common issues like unwanted bursts in semi-auto mode when using high-voltage batteries.
Many MOSFETs are programmable, allowing users to customize firing modes such as 3-5 round bursts or Turbo Shot, which fires on both trigger pull and release. These features offer tactical advantages in CQB or SQB matches, though they remain subject to game regulations. Upgrading to a MOSFET also enhances the tactile feel of the trigger, often replacing it with a more responsive microswitch. Available in various types and manufacturers, MOSFETs typically utilize magnet or optic sensors, further refining the performance of gel blasters and tailoring them to different playstyles.