The V4 has a slot that allows you to work with thicker wire that won't go through the hole. Otherwise it works the same as the V3. If you're really into building RDAs you'll want this, especially at such a great price. Another home run from Coil Master!
Are you 18 or older & of the legal smoking age in your state?
It's easy, select Autoship at checkout! No coupons necessary!