When it comes to refillable concentrate vape pens, CCELL leads the way with breath-activated batteries that are some of the smallest available. The cartridges are made of Inert materials, like a glass housing and ceramic wick and mouthpiece, to deliver pure flavor. The wickless design can vaporize thick or runny concentrates. The CCELL M3 battery is only three inches long, and is the ultimate in portability and discretion. Forget clumsy buttons and settings - all you do is inhale from the mouthpiece for thick, comfortable vapor in an instant. The CCELL M3 mates perfectly with CCELL cartridges, like the TH2 or M6T. Some off-brand 510 threaded atomizer don’t work on this battery. If you’re looking for a refillable portable vaporizer for concentrates, the CCELL system is as good as it gets. The modular system offers different sizes and looks, and the quality is top-notch. With very affordable pricing, this is one of the few times it doesn’t pay to get anything less than the best.