Honest review time The Lock RDA from EHPRO

Here’s a look at a recent RDA release from EHPRO sent over from Buybest for review. Buybest if you’re not familiar with them are a company out of China with great deals on all sorts of things much like Gearbest or Fasttech. This new RDA released by EHPRO is just one of several devices that have made a return to notch coils. If you follow my reviews you might have seen an RTA review involving notch coils which I was quite impressed with so I’m naturally curious to see how others have re-implemented this somewhat older coil technology. Notch coils if you’ve never heard of them are cylindrical metal tubes with notches cut out of them to form a rudimentary coil. They were made popular a couple years back with the release of the Theorem a notch coil based RDTA co-designed with Wismec and SuckMyMod. They were immensely popular for a while and then sort of drifted from the mainstream only to return a couple years later in a few new re-imagined incarnations. While notch coils aren’t really anything new this RDA from EHPRO that uses them is so here are my honest thoughts on the Lock RDA from EHPRO.

Package contents:

Lock RDA1
Squonk pin1
Notch coil2
Hex screws2
Allen key1
User manual1
Warranty card1
Certification card1

Listed features and specs:

  • Easy and convenient refilling design
  • Easy building of coil
  • Honeycomb style 810 drip tip with excellent tactile impression
  • Squonk pin to make it suitable for squonk mods
  • Side-up direct airflow to deliver pure flavor
  • Dimensions: 24.0 x 28.0mm
  • Material: Stainless steel, Resin

Packaging and Contents:

The kit comes packed in a little black cardboard box with a window on the front so you can see the RDA inside. On the back there is some caution text, a sticker to denote the model as well as provide a security check and that’s about it. I’d have liked to see the contents and special features listed but it’s a minor complaint. Inside you get the Lock RDA, a box of extras, a QC card, a warranty card, a warning card and a user manual. Inside the box of extras you get two notch coils, two spare grubs, three spare orings, an Allen key, a 510 drip tip adapter, a gold plated squonk pin and a little pack of cotton. The kits contains everything you’d need to get started and it all arrived safe so no complaints here.

The Lock RDA:

The Lock RDA is a pretty beefy looking dripper that’s 24mm in diameter and stands around 28mm tall. It’s made of stainless steel and comes equipped with a honeycomb resin 810 drip tip. The outer design appears really simple with a two part top cap which allows you to adjust the airflow. The cap is notched on the interior so once it’s in place it only slides back and forth enough to adjust the airflow and that’s it. Three little holes on each side provide the airflow to the deck but can be closed off by turning the upper portion of the top cap. The upper half of the cap is shaped like the head of a bolt to help turn it while the lower half is round like a typical top cap. On one side it’s got a nicely engraved logo with Lock written underneath. The engraving is fairly deep and looks nice without any rough or sharp edges anywhere. It’s available in two colours, I got the black version which so far has been holding up to wear an tear. On the very bottom of the RDA it’s got a serial number and the words ‘Designed by Ehpro’ as well as the usual CE markings. The threads on the 510 connection are nice and smooth and it comes with a gold plated 510 squonk pin if you like to squonk. From the outside like I said it’s a very simple looking RDA but it’s what’s inside that makes it special.

The Deck:

The deck on this thing looks familiar as it isn’t the first notch coil deck I’ve seen. At it’s core there is a little metal cradle that holds the notch coils in the center of the deck. The notch coils press fit in to the cradle to ‘lock’ in to place. It’s one of the easiest setups I’ve ever used and you can get a coil installed and wicked in less than a minute if you know what you’re doing. The deck has a really deep juice well but the cradle takes up a good portion of it. In the well on each side the base of the cradle sort of blocks off most of the accessible well so when wicking it I’d suggest splitting your wicks in two and tucking them in on each side of the cradle base so your liquid doesn’t have to travel around the cradle walls to get to your cotton. This also affects how it squonks as the juice comes up in the middle of the cradle but doesn’t make direct contact with your cotton unless you wrap it around the base like I suggest. I think they should have drilled a hole or cut out some of the extra metal from the bottom of the cradle base to let the juice get to the outer edges of the juice well and not have to go around. Basically instead of walls they should have used little trellises which would have still given it the support it needs but would have let the liquid flow in the deck.

A very cool feature that wasn’t very obvious at first was the inclusion of regular post slots on the inside of the cradle. This actually allows you to build the deck with regular wire coils if you run out or if notch coils just aren’t your thing, a really handy little feature and it helps make this thing a lot more versatile. However because there are only two little post holes it’ll pretty much be single coil only unless you get a little creative with coil placement. The way this thing was built though it’s pretty much meant for single coil. To tighten your leads when using a regular coil two little gold plated grubs are accessible from each side. Airflow to the deck comes via three holes on each side which line up with the three holes on the top cap. You can turn the top cap to close off some or all of the holes but I found it pretty comfortable at full open for a very slightly restricted direct lung hit. The three holes that cut through the deck are angled downwards to direct the air to the lower portion of the coil but also to help prevent leaking or over-squonking. The way they line up they pretty much hit the lower sides of the coil so air will be forced up and over the coil which to me is ideal when it comes to getting the most flavour out of a coil.

Build, Wick and Performance:

There really isn’t much to talk about in this section as you don’t really build on it, you just pop in a notch coil, run your cotton through it, tuck your cotton in to the well and that’s it. It’s one of the easiest devices to work on and maintenance overall is basically a breeze. Wicking it does require a considerable amount of cotton because the inner diameter of the notch coils is fairly big but once you figure it out it’s like wicking nearly any rda out there. As I mentioned above I would recommend splitting your wicks in two because the cradle take up quite a bit of room in the juice well. The notch coils being made of SS should last quite a while but if you need to clean one off you can dry fire it at very low wattage or torch it with a lighter to burn off the gunk. In either case be careful not to over do it as the coils are a bit delicate if overheated. If you try and run too much power through them they’ll likely hotspot and melt as they aren’t really meant for high wattage vaping. The coils are rated around 0.2ohm with a suggested wattage range of 30-50w with the sweet spot for me being around 40-45w. I found they gave a pretty good balance of flavour and clouds but a lot of that will ultimately depend on the juice you are using and how you are running it.


  • Looks
  • Build quality
  • Innovative deck design
  • Notch coils or regular coils
  • Anti-leaking air holes
  • Notched top cap
  • Squonk pin included
  • Notch coil performance
  • Great flavour and vapour
  • Ease of use!!!


  • Cradle takes up too much room in the juice well


While I think the cradle design could be slightly improved I was pretty impressed with the Lock RDA as it stands. It works really well with the 0.2ohm notch coils and doesn’t require a lot of power to operate. It produces nice satisfying flavour and vapour and on top of all that it’s one of the easiest decks to work on. I know notch coils at one time were a sort of fad and they likely aren’t for everyone but with these new implementations I think they’re definitely worth revisiting for both new users and seasoned users alike. The convenience and experience make them well worth checking out and I wouldn’t have any issues recommending the Lock RDA to anyone looking for just such a setup.