Honest review time: The Marvn RTA from Coil Master

Recently I reviewed a DIY kit from a company called Coil Master. They’ve been around for quite some time now and are probably best know for their DIY kits and their 521 tabs but they’ve also been releasing some interesting gear like mech mods and some RTAs. I was fortunate enough to be sent a few items from CM and the latest is an RTA tank called the Marvn. Here are my honest thoughts on the Marvn from Coil Master.

Package contents:

Marvn RTA1
Extra glass1
Extra screws2
Clapton coil2



Listed features and specs:

  • Funnel-shape designed Delrin Drip tip
  • Air-releasing Top fill design
  • Dual adjustable air flow control
  • PEEK insulator
  • Gold plated bottom pin & base
  • 304 Stainless steel
  • 25mm in diameter for Glass tank
  • Max 26mm in diameter for Deck
  • 43.5mm in height (not including drip tip and 510 contact)
  • Capacity: 5ml
  • Weight: 65g



The Marvn RTA Tank:

The Marvn rta is quite big, it’s made of 304 stainless steel, has a 26mm diameter, stands 43.5mm tall not including the drip tip or 510 connection and holds a very comfortable 5ml of liquid. Starting at the top it comes equipped with a wide bore delrin 810 drip tip that’s nice and comfortable on the lips and does a fine job of dissipating heat. Just below the drip tip is the top fill cap. Unscrewing it reveals two large kidney shaped holes that you won’t have any trouble filling up with. They’re wide enough to accommodate the largest of bottle tips and I haven’t had any issues with it in the weeks I’ve been using it. They claim it is air-releasing which I imagine will help prevent flooding when putting the cap back on. It’s done a good job of not making a mess when filling it and rarely would I need to wipe up any excess liquid after a refill. As mentioned above it comes with a spare 5ml glass tank so if you happen to break one you’ll have an extra. It breaks down fully for cleaning and all of the threads on the tank are buttery smooth.

The airflow to the deck comes via two large cyclops style slots on the bottom of the tank. It’s adjustable using the airflow control ring which goes from full open to closed with stops at either end but not clicks to hold it in place. It’s fairly firm and hasn’t moved around on me accidentally. At full open it provides a nice slightly restricted direct lung hit which is how I’ve been running it. On the bottom it’s got a non-adjustable 510 pin that looks gold plated and protrudes just enough you could safely use it on a hyrbid connection.

The deck:

The deck on this thing is sort of a mix of old and new. It sports u-shaped clamps for clamping down on your leads, triangle shaped airflow slots to feed your coils and easy to use wick channels for your cotton. The u-shaped deck clamps can be a bit of a challenge when building as you’ll need to lift them up to get your leads underneath as they’re not spring loaded. Either that or you can hold it upside down and let gravity do the work. I’m fairly used to this but it’s something to be called out as it might be challenging for new users. This style of posts might limit the types of builds you can fit in but I’ve so far not had any issues with the included fused claptons, a straight 22g wire build and some homemade fused claptons I popped in.


Build, Wick and Performance:

Building on this thing is pretty straightforward and if you’ve got almost any amount of experience building RTAs you should be right at home. There might be a slight adjustment with the clamps as mentioned above but aside from that it’s pretty standard stuff. Clamp your leads in the posts, might have to stack them depending on your coil selection, cut off any excess leads, wick it like you would most other RTAs or RDAs using the provided wick channels to guide you. I found they require quite a bit of cotton to fill them up and if you leave them a bit too loose or thin you might end up with some leaking. Performance wise it works great, I really like the airflow and rock it pretty much full open for a very slightly restricted direct lung hit. Flavour from this thing has been fantastic for a dual coil RTA and I found it very similar to it’s predecessor the Ray RTA also from CM. As with most things performance will ultimately depend on the build you are using but just using the included coils alone I found it performed like a champ.



  • Flavour and vapour
  • Capacity
  • Build quality
  • Ease of use
  • Airflow


  • Deck clamps are a bit tedious to work with
  • single coil adapter


I really enjoyed testing out and using the Marvn, it’s a pretty simple, easy to use, good performing RTA without many bells and whistles. Considering it’s 5ml capacity it should be a boon for capacity junkies that enjoy using big tanks. I tend to prefer my gear compact but definitely have a place for large capacity tanks for things like long road trips or days spent working on projects outside. While it doesn’t offer anything particularly unique it does what it sets out to and does it well. So the big questions as always:

Will I keep using this thing? Absolutely, it’s a great performing RTA that’s easy to maintain and has the benefit of a large 5ml capacity.

Who do I think this is for? I think this one will be mostly for seasoned vapers who like to use rebuildable tanks with big capacities but it could also be a good entry point for those just getting in to building as it’ll be pretty easy for a beginner to tackle.