Top-Fill Tanks: The modern standard for tank design. The top cap swivels, slides, or lifts open to reveal large fill ports, making refilling e-liquid quick, easy, and mess-free. This is a critical user experience feature that has largely replaced older bottom-fill designs.

Cotton Coil Pods: The traditional and most common wicking material. Organic cotton is highly absorbent and provides a warm, familiar vapor quality. Advancements in cotton purity and braiding techniques continue to improve flavor and longevity in modern pod coils.

18650/21700 Batteries: Standardized, cylindrical lithium-ion cells that are removable and rechargeable. The numbers refer to their dimensions (18mm x 65mm, 21mm x 70mm). They are the power source for advanced mods, with different models offering trade-offs between capacity (mAh) and maximum discharge current (A).

E-Liquid Box Packaging: Smaller cardboard boxes designed to hold a 30ml, 60ml, or 120ml glass or plastic e-liquid bottle. They provide protection from light (which can degrade nicotine and flavor) and offer ample space for branding, ingredient lists, warnings, and government-mandated tax stamps.

Pod System Box Packaging: Higher-end cardboard boxes for pod starter kits. These often have a magnetic closure or sleeve and internal foam or plastic inserts to securely hold the device, pods, and accessories. The box design is crucial for communicating brand quality on a retail shelf.