SD Keyring

SD Keyring

The SD Keyring…candy and tank for size comparison

The SD Keyring is a stealth PV mod created by Trog, who brought us the original Screwdriver PV mod. At only 44mm without cartomizer, this is a very small device, and is easily concealable for “undercover vaping”, and extremely portable as a backup.

The unit is rated at 300mAh, and comes complete with a USB charger, and two prefilled cartomizers.

SD Keyring

Only slightly larger than a cartomizer, and smaller than a roll of candy, the SD is tiny.

Impressions of the SD Keyring from Trogsd key ring

Sometimes, good things do come in small packages.

Okay, we can see this PV is portable, but how does it vape?

First things first…the packaged prefilled cartomizers aren’t the best tasting, but are easily replaced, of course.

The compact battery is rated at 300mAh, and from my vaping, seems to be inline with this claim. At just under a full charge with my DCT, I was able to measure the output voltage at 3.32v. I was unable to get a reading at full charge.

Because this is an automatic battery activated when inhaling, there is no need for a shutoff switch. It is also not conducive to using with atomizers, as they will continue to burn beyond inhalation.

With a cartomizer or tank though, this small package does indeed provide big things. It produced surprisingly good vapor volume and taste from my carts and tanks.

One thing I managed to find out while testing this device, it will automatically shutoff after approximately 5 seconds of activation. No, you still shouldn’t use atomizers!

stealth vaping

Where did my SD Keyring go? Oh…it’s under my tank!

Sitting under my Depth Charge tank, this PV looks freakishly small!

comparison of the SD Key Chain

Left: SD Keyring with Super T stainless drip tip Right: Stock Cartomizer

You can outfit the SD mod with whatever you like (not including atomizers)…be careful though, it could get top heavy!

What I think of the SD Keyring

Nothing I would rely on, or recommend to someone who is entering the eCigarette scene by far. If your looking for a simple, backup device, this might fit the bill.

The Good

  • Size – The SD Keyring is the stealthiest of them all.
  • Price – Awesome performer for the price.
  • Activation – Auto “suck” activation is convenient for a stealth vape.
  • Size – Did I already say this thing is really small? Sometimes, good things do come in small packages.

The Bad

  • Because this is such a small device, it could easily be lost?

The Ugly

  • Nothing.

Final notes on the SD Keyring
No, it’s not an all day vape, nor is it the most flexible PV mod. But than again, it wasn’t meant to be. The SD Keyring is a conveniently small device that performs great as a stealth vape, or used as a backup.


  • Name: SD Keyring
  • Price: $19.95(Body Only)
  • Switch: Auto “suck” switch
  • Battery: 300mah
  • Connector Type: 510
  • Body: Unknown
  • Warranty: Unknown

What you get in the package:

  • 1 x SD Keyring ecig battery
  • 2 x pre-filled cartomizers
  • 1 x USB powered automatic charger
  • 1 x lanyard tether (attached to battery)

Bottom Line: Small, simple to use, decent looks, satisfactory battery time for its purpose…stealth vaping never seemed so…stealthy.


  • Alex says:

    HI ! And good review of the SD Keyring. I recently bought one and I’d like to use a Tank on it (look very nice on your pictures). Can you tell me what kind of pre-punched carto (I mean, which resistance) do I have to use?
    Thanks in advance for your answer.

    • TUC says:

      Because it is a low voltage device, you need a low resistance cartomizer for best results…1.5 or 1.8 Ohms.

      • Alex says:

        Thanks TUC. I’ve tried with a 1.5ohm resistance carto. It produces very low vapor (sorry for my english, I mean less vapor than the carto sold in the pack with the SDKeyring). Maybe you are talking about carto with single coil resistance. I’ve tried with double coil (the final resistance is 1,5ohm). Could you give me the configuration of you tank? Single/dual coil? Resistance 1,5/1,8/2.0 ohms?

  • TUC says:

    Vapor production is a large result of the juice used also. The tank used in the picture was a 1.8-2.0 ohm dual coil cartomizer.

  • Jay says:

    Hi, how bout the battery life, how long would it take if you are using 1.8OHM dual coil cartomizer?

    • TUC says:

      Hi Jay, battery life is not long at all. I only use this as a backup…not a primary vape, by no means.

  • hanglider says:

    Unsealed, sure-to-short connection and automatic operation. I’ll pass.

Comments are closed.