This battery has a triangular design with three sides and a slim button. With a 500mah capacity, this battery won't have you searching for a charger so quickly. Both the pass-thru port and the Trigon's threaded connection may be used to charge the device. Temperatures range from 2.7 to 4.2 in its five settings. Preheat and overcharging safeguards are built into each battery's design. As an added measure of security, the battery is protected by a timer set to shut off after 12 minutes of inactivity. Between the appearance, the feel, and the quality, In terms of prefilled carts, the Power Trigon is the best 510 thread pen on the market. It's slick and elegant, and it hits like a champ.