GeekVape 521 Tab Coil Master, designed to increase the degree of safety and avoid building a dangerous coil for the mod you are using. SPECIFICATIONS: Size: 93.6mm*75.4mm*24.7mm Resistance Measuring Range: 0.01 – 9.9Ω Lowest resistance rate: 0.1Ω Connection : 510 elastic poles Battery: Lithium 18650, 3.7V (Batteries are not included in the product) FEATURES: Reverse battery protection Low-voltage protection Short circuit protection Breaker protection Low resistance High temperature protection If you are interested in this Digital 521 Tab Coil Master, please pay a close attention, it will be available soon at heavengifts.com. BTW, as always, please feel free to play your order by using our 8% off coupon code: AHGEVAPE For more info of the Digital 521 Tab Coil Master, visit here: http://www.heavengifts.com/GeekVape-Digital-521-Tab-Coil-Master.html