Brass Knuckles Pen Battery

Functions of the battery:

• 2 click preheat mode.
• More Power 20 seconds hold time.
• Adjustable voltage : 3.3 v – 4.1v
• Press twice to preheat for the extra thick oil
• Volume: 900 mAh
• Length: 95mm
• Diameter: 11.2mm
• Weight: 22g
• Compatible with any 510 thread cartridge
• Preheating output: 1.8v
• Display of 30 vape batteries