Penjamins | Discreet Vape Pens & Stealth 510 Cart Batteries

If you've seen the word "penjamin" on social media and wondered what it means, you're not alone — and you're in the right place. A penjamin (also styled as "Penjamin Franklin") is slang for a discreet, portable cannabis vape pen — particularly sleek, compact devices designed to look like everyday objects and hide in plain sight. The term caught fire on TikTok and quickly became the go-to name for any low-profile, pocket-sized device used with oil cartridges or pre-filled concentrate.

At DiscreetSmoker.com, we carry a selection of penjamin-style vape pens, stealth 510 thread batteries, and discreet cart devices — compact, rechargeable, and designed for maximum discretion. From pen-shaped 510 batteries that double as real writing instruments to ultra-slim draw-activated devices roughly the size of a mini BIC lighter, our penjamin collection features the most discreet ways to enjoy oil cartridges without drawing attention.

Browse the full penjamin collection below.

What Is a Penjamin?

A penjamin is a discreet vape pen for cannabis oil, concentrates, or THC cartridges. The term is a portmanteau of "pen" and "Benjamin" — often punned as "Penjamin Franklin" — that originated in social media meme culture. What started as playful slang quickly became the widely recognized name for an entire category of ultra-discreet cannabis vaping devices.

In its broadest sense, "penjamin" can refer to any compact, discreet vape pen — including all-in-one disposable vapes, slim 510 thread batteries, and stealth devices disguised as everyday objects like pens, key fobs, or lighters. The common thread across all penjamins is discretion: these are devices designed to be small enough to hide in your hand or pocket, inconspicuous enough to use without attracting attention, and simple enough to operate with little to no learning curve.

The term is most popular among Gen Z consumers and the broader social media cannabis community, but the devices themselves appeal to anyone who values privacy, portability, and simplicity when using oil cartridges. Whether you call it a penjamin, a cart pen, a stealth battery, or just a discreet 510 — the concept is the same: a vape that nobody notices.

Types of Penjamins

Pen-Style 510 Batteries (Writing Pen Disguise) — The most literal interpretation of the penjamin concept. These are 510 thread batteries built inside a real working ink pen. The Smyle Labs Penjamin Cart Pen is the original and best-known example — it writes with actual ink (twist the bottom to extend the ballpoint tip) and conceals a 510 cartridge inside the pen body (remove the cap to reveal the connection). Features typically include adjustable voltage settings, preheat functionality for thick oils, and USB-C rechargeable batteries. When the cap is on, the cartridge is completely hidden and the device looks exactly like a standard pen. These are the ultimate stealth option for people who need their vape to be genuinely invisible — on a desk, clipped to a notebook, or in a shirt pocket, nobody would ever suspect it.

Key Fob 510 Batteries — Stealth 510 batteries disguised as car key fobs. These clip onto your keychain and conceal a standard 510 cartridge inside a chassis that looks exactly like an automotive key fob with lock/unlock buttons. The "buttons" serve as fire controls for the battery. Key fob penjamins typically support 0.5g and 1g cartridges, offer adjustable voltage, include preheat, and charge via USB-C. Like pen-style penjamins, the disguise is convincing — the device blends seamlessly with your actual car keys.

Slim Draw-Activated 510 Batteries — Ultra-slim 510 thread batteries with no visible buttons, designed to be as small and inconspicuous as possible. Many are draw-activated (inhale-activated), meaning there's no button to press — just attach your cartridge and inhale to fire. These batteries are often no larger than a mini BIC lighter or a standard pen, making them easy to palm, pocket, or conceal in a closed hand. While they may not be disguised as a specific object, their sheer smallness and simplicity make them functionally invisible.

All-in-One Disposable Penjamins — Pre-filled, pre-charged disposable vape pens that come ready to use right out of the package. These contain both the battery and the cannabis oil in a single sealed unit — no cartridge to attach, no settings to adjust. Just inhale. The Franklin Fields Penjamin is a notable example: a compact all-in-one disposable featuring live resin extracts, USB-C rechargeability (to ensure you use every drop of oil), clog-free technology, and a form factor roughly the size of a mini BIC lighter. All-in-one penjamins are the simplest, most hassle-free option — nothing to screw on, nothing to charge (though many include USB-C for topping off), and nothing to maintain. When it's empty, you dispose of the entire unit. Note: all-in-one disposable penjamins with cannabis oil are only available at licensed dispensaries in legal states and are not sold through our store. We carry the reusable 510 battery devices that pair with your own cartridges.

Novelty & Disguise 510 Batteries — The penjamin concept has expanded beyond pens and key fobs into a wide range of creative disguises including miniature purses, wands with LED lights, lighters, inhalers, and even remote-controlled robots. These novelty stealth batteries all use standard 510 threading and conceal your cartridge inside the disguise object. They add fun, personality, and conversation-starter appeal to the stealth battery category while still delivering the core penjamin value: nobody knows it's a vape.

What to Look For in a Penjamin

Cartridge compatibility. Make sure the penjamin supports the cartridge sizes you use — most accommodate standard 510 thread carts in 0.5g and 1g sizes. Some devices include an adapter for smaller cartridges. Check that your cartridge's diameter fits inside the concealment cap or chassis if full concealment is important to you.

Voltage settings. Adjustable voltage gives you control over your vapor — lower settings (2.0V to 3.0V) deliver smoother, more flavorful draws while higher settings (3.2V to 4.0V) produce thicker clouds and stronger effects. Three-setting variable voltage is standard across most penjamin-style 510 batteries. Some ultra-slim draw-activated models use a single preset voltage for maximum simplicity.

Preheat function. A preheat mode gently warms your cartridge at low voltage for 10 to 15 seconds, which loosens thick oils, prevents clogs, and primes the cartridge for a smooth first draw. This feature is especially important if you use thick distillates, live resin cartridges, or vape in cold weather. Most pen-style and key fob penjamins include preheat; some ultra-slim batteries do not.

Charging. USB-C is the current standard and offers the fastest recharge times (typically 15 to 30 minutes). Some older models still use micro USB. Rechargeable batteries are standard across all reusable penjamins. Always use a standard 5V power source — never use fast-charge phone adapters. Check our vape chargers collection for compatible cables.

Battery life. Compact penjamin batteries typically deliver 200 to 400 puffs per charge depending on voltage settings and draw length. The Smyle Labs Cart Pen is rated for approximately 350 puffs. Moderate daily users can generally get a full day from a single charge. If you're a heavy user, consider keeping a backup charged.

Level of disguise. Some penjamins are designed for total stealth — pen-style batteries that write with real ink, key fobs that look exactly like car keys. Others prioritize slim minimalism without a specific disguise — they're small and inconspicuous but still recognizable as a vape up close. Decide what level of discretion you need for your typical use environment.

Draw activation vs. button activation. Draw-activated (inhale-activated) penjamins require no button press — just inhale and the battery fires automatically. This is the simplest operation possible and eliminates accidental firing. Button-activated models give you more control (preheat, voltage adjustment, manual fire) but require learning a few click sequences. Most pen-style and key fob penjamins are button-activated; many ultra-slim batteries are draw-activated.

How to Use a Penjamin 510 Battery

Attach your cartridge. Screw any standard 510 thread oil cartridge into the device's connection. For pen-style penjamins, remove the cap first to access the 510 thread inside. For key fob styles, remove the top portion and drop in the cartridge with the included magnetic adapter. Don't overtighten — screw until snug.

Power on. For button-activated models, click the fire button 5 times rapidly to turn on. An LED indicator will flash to confirm. For draw-activated models, simply inhale — no power button needed.

Adjust settings. Click the button 3 times to cycle through voltage settings (LED color changes to indicate the current level). Click 2 times to activate preheat mode for thick oils. These controls are consistent across most 510 penjamin batteries.

Inhale. Hold the fire button (or simply draw for auto-activated models) and inhale slowly and steadily through the mouthpiece. Start with short draws to gauge vapor production and flavor before taking longer pulls.

Conceal. After your session, replace the cap (pen style) or top piece (key fob style) to fully hide the cartridge. Slip the device back into your pocket, clip it to a notebook, or set it on your desk — it blends right in.

Charge. Connect the included USB-C cable to the charging port when the LED flickers or your hits feel weak. Full charge takes 15 to 30 minutes. Use a standard 5V source only.

Who Should Buy a Penjamin?

Penjamins are for anyone who uses 510 oil cartridges and wants the most discreet possible experience. If you vape at work, in public, while traveling, around family or roommates, at social events, or in any setting where you'd rather not broadcast that you're using a vape, a penjamin is built for exactly those situations. They're especially popular among younger consumers who grew up with the term on social media, but the appeal of discretion is universal across every age group.

Penjamins also make excellent gifts — the surprise factor of revealing what the device actually does makes for a memorable unboxing, and the affordable pricing (most penjamins are under $35) puts them solidly in gift-giving territory. The wide range of colors and designs means you can match the gift to the recipient's personality.

Pair your penjamin with compatible cartridges and browse our full 510 battery, vape charger, and smoking accessories collections.

Frequently Asked Questions