3 FINISHESSide by side
Ooze Twist Slim Pen 2.0 vs EF420 Vertex
Both of these are 510-thread batteries, both recharge, both ship with a USB charger, and they sit close together on price. On paper that reads like a coin toss. It is not — one of them carries nearly three and a half times the battery of the other, and the other is the one you can actually get in a colour you like. Here is the whole decision.
5 min readUpdated August 12, 2026
Specs, side by side
Every figure below is the one published on each product page. A highlighted cell is the side with the clearer advantage on that row.
| Spec | Ooze Twist Slim Pen 2.0 Battery |  EF420 Vertex 1100mAh Vape Pen |
|---|---|---|
| Price | From $17.99 | $19.99 |
| Format | 510 battery | 510-thread vape pen battery |
| Battery | 320mAh rechargeable | 1100mAh rechargeable |
| Voltage control | Flex Temp variable voltage dial | Adjustable voltage + preheat |
| Connection | 510 thread | 510 thread |
| Charging | USB charger (included) | USB, charger included |
| Material | Not listed | Metal |
| Finishes | Several | Silver only |
The capacity gap is the headline
1100mAh against 320mAh. The Vertex carries roughly 3.4 times the charge of the Twist Slim, for two dollars more.
There is no reading of that where it is a close call on capacity alone. If how often you have to charge a thing is what you care about, the comparison is settled in the first row of the table.
What the Twist Slim is actually for
Its name is the argument. The Twist Slim 2.0 is built around being slim, and a 320mAh cell is a large part of how it gets there — a battery that carries 3.4 times the charge is not going to be the same shape.
It also comes in several finishes where the Vertex is silver only. That sounds trivial until you own one, since this is an object that lives in a pocket and gets taken out in front of people. Ooze offers the choice; EF420 does not.
The Flex Temp dial is a genuine variable-voltage control, not a two-position switch. On voltage adjustment specifically these two are closer than the price gap suggests.
Preheat is the feature the Vertex has and the Ooze does not
The Vertex lists adjustable voltage *and* a preheat setting. The Twist Slim lists the Flex Temp dial and no preheat.
Preheat is a short low-power burst applied before a draw, and it exists because thicker extracts do not move well when cold. Whether you need it depends entirely on what you put on the battery, which is your decision to make and not ours to assume.
What is in the box
Both include a USB charger, which is worth confirming rather than assuming — plenty of 510 batteries do not. The Vertex listing spells out its contents as the 1100mAh battery plus a USB charger; the Ooze listing states a USB charger is included.
Neither contains nicotine, cannabis or e-liquid. They are hardware, and what you thread onto them is separate — including whether it is legal where you live, which is your responsibility to confirm.
The verdict
Which one, for who
You want the battery that lasts longest between charges
EF420 Vertex 1100mAh Vape Pen1100mAh against 320mAh — roughly 3.4x the capacity, for very little more.
You want the smallest thing that does the job
Ooze Twist Slim Pen 2.0 BatteryThe slim pen form factor is the point of it, and the 320mAh cell is how it stays that size.
You want a preheat setting
EF420 Vertex 1100mAh Vape PenThe Vertex lists preheat alongside adjustable voltage. The Twist Slim does not.
You want a choice of finish
Ooze Twist Slim Pen 2.0 BatterySeveral finishes against the Vertex's silver only.
You want the cheapest working 510 battery
Ooze Twist Slim Pen 2.0 BatteryA variable voltage dial and a charger in the box, at the lower price of the two — though not the better value per mAh.
Common questions
Which has the bigger battery?
The EF420 Vertex, at 1100mAh against the Ooze Twist Slim's 320mAh — roughly 3.4 times the capacity.
Do both have variable voltage?
Yes. The Twist Slim has a Flex Temp variable voltage dial; the Vertex lists adjustable voltage plus a preheat setting the Ooze does not have.
Do they come with a charger?
Both include a USB charger.
Will they fit any 510 cartridge?
The 510 thread is a standard, so they connect to 510 cartridges generally. Nothing is included with either battery — you supply what goes on it.
Do these contain nicotine?
No. Both are hardware only, with no nicotine, no e-liquid and no cannabis.