As a fan of the MTL version, the MoMoVaping website was kind enough to send me the Diplomat RDL free of charge, without having any working relationship with them or receiving any payment. This is a shop focused on rebuildable styled atomizers and accessories like drip tips, in addition to having a rich offering of hard-to-find pyrex tanks, both for RTAs and for some coil-head atomizers that are now unobtainable, like those for Hellvape.



The steel finish is entirely polished/glossy. The capacity of the Diplomat RDL varies depending on which bell is installed, with the largest (Duke) allowing for 5.7 ml and the Volcano for 6.2 ml. It weighs 52 grams excluding the drip tip, has a diameter of 23 mm, and a height of 41 mm, also excluding the drip tip and 510 pin.



The transparent packaging contains the entire kit, with a "MoMo" sticker on top. Inside are the two bells (plus a third one installed): Duke, Volcano, and Poker, two pyrex tanks (one installed, one packaged), four airpins, and a fifth one pre-installed. There's a generous supply of o-rings, spare screws, and the inevitable blue screwdriver.



The drip tip also features a mirrored finish with a base and two dissipators to keep heat under control. The bore width is 5.5 mm, while the height, excluding the base, is 13.3 mm. The drip tip insert is standard size; trying other drip tips, almost all fit without protruding or straining the o-rings. On the top cap of each bell, there's a slightly different machining compared to the MTL version, which more than for increasing grip, also serves to dissipate heat.



The bell assortment is different from the MTL version, both for the chosen models and because the chimneys, as will be seen, are wider. The Diplomat RDL sold by MoMoVaping includes the Duke, Volcano, and Poker bells, from left. It's clear from the outside that the volume varies, which is quite different from atomizers that only have an interchangeable top chamber. The steel finish is completely polished. I also remind you that they are a single piece of steel, with no separate top cap (meaning bottom refill). The Duke weighs 19 grams, while Volcano and Poker weigh 18 grams each.



Internally, it should be clear that the chimneys are between 0.5 and 1 mm wider than the MTL version; these are the measurements, keeping in mind a 0.1 mm inaccuracy since I don't have a professional caliper. The internal diameter is taken after the threaded part that connects to the deck ends.

Duke: chimney width 5.0 mm, diameter 15 mm
Volcano: chimney width 4.6 mm, diameter 14.6 mm
Poker: chimney width 4.4 mm, diameter 13.7 mm

The most interesting part, and one I had doubts about, is that the threading is identical to that of the MTL version's bells and base. I used both the RDL version's bells on the MTL base and vice versa (RDL base with MTL bells), and everything seems to work perfectly.



Photo without tank to better show the fixed liquid intake slot, thus without JFC and wider than the MTL version, and perfectly sized for what the Diplomat RDL needs to do. Just below, one of the fixed air slots that allow air to enter. The pyrex tank is held between the two parts, sealed by the o-rings. Replacement pyrex tanks are also available on MoMoVaping.



The first major difference from the MTL version is the airflow system. Here it's fixed, so there's no airflow ring; everything is managed by the airpin used, which collects air entering from the two slots seen above. Fortunately, MoMoVaping also offers several airpins with the Diplomat RDL: 2, 2.5, 3, 3.5, and 4 mm (pre-installed), which cater even to those who appreciate an open MTL. They can be unscrewed with a flat-head screwdriver with a deep recess that prevents the tip from slipping, and they also have the measurement engraved on the pin.



The second difference is the coil walls, which allow the use of complex coils, making installation easier for fans. The airpin also protrudes much higher, and the two wicking channels remain connected, not separated. Coil placement is perhaps even easier thanks to the walls, with screws that provide a good grip, and you just need to place the wire between the screw and the wall to tighten it. Refill, in this version, is solely from the bottom.



Unscrewing the airpin releases the positive post and the base, held in place by an o-ring under pressure and with two wings that keep it secure in its seat. When replacing the airpin, you need to transfer the PEEK insulator onto the airpin you want to use each time. Another insulator is installed (I believe) by pressure and holds the post. It provides enough friction and seal, so the post should remain in position if you want to replace the airpin with a build already mounted and a full tank.



The P.A.S.S. system, already adopted on the Diplomat MTL, is slightly different, featuring a double row of airflow holes, which should be less than 1 mm, silencing and eliminating air turbulence entering from the two side airflows before being channeled into the airpin. As a solution, it works; it still makes a bit of noise, but it's acceptable with wider holes like 3 mm and above. Thanks to the 2 and 2.5 mm airpins provided by MoMoVaping, it can also be used for an open MTL.



Duke: the chamfer near the chimney is slightly less pronounced than the MTL version. In RDL, it's also the most suitable of the lot for complex cream flavors, given its aromatic spectrum. If you have the Duke MTL, I don't consider it a duplicate. Volcano: mainly designed for NET tobaccos and to filter out sweeter notes; in RDL, it can be used for VCTs if you don't want to perceive too much of the sweet flavoring. Poker: aesthetically similar to the Rhodesian but enhances the top note in a slightly different way. It leans towards sweet; in RDL, it performs well with creamy and fruity flavors.

Build: if you want to use it for a normal open MTL with the 2 mm under-coil hole, a 27g wire, on a 2.25 or better 2.5 mm internal diameter with 5 or 6 wraps, offers a warm/hot vapor that pairs well with tobaccos. With the 2.5 mm airpin, however, a 26g wire starts to be necessary, as the air intake becomes quite substantial. In RDL with the 3.5 or 4 mm hole, I imagine the limit is around 35 watts, as the chimneys of the bells are wide but not excessively so. You can achieve this by using a complex coil, as there is space to install them. For the number of wraps, 6 fit, for 7, you need to start spacing them closely / going for a micro coil.

Draw: despite the different air intake method, it remains a slightly tighter atomizer than the hole used, thanks to the airpin directing air towards the coil as it enters the deck. With the 2 mm airpin, I believe it's still within the limits of MTL vaping, considering how many famous pure MTL atomizers have a similar hole. Necessarily, the 2.5 mm one is even more open, and so on. The 3.5 and 4 mm are for a restricted RDL without exaggeration. The incoming air makes a bit of noise in the very initial section; the double-row hole system significantly silences it, and when the air enters the deck, there are no turbulence phenomena or excessively fast entry, hence the above-average lifespan of coils and cotton even when using extracts.



If you are a fan of the Diplomat MTL, the feeling of simplicity and immediacy, given that here too there are only two main pieces plus the drip tip, remains unchanged. That "RDL" in the name might suggest a very open atomizer, but that's not the case. Conversely, if you are a fan of a very open MTL or RDL draw, the Diplomat RDL is one of the few to adapt the multi-bell concept developed in MTL vaping and translate it into a more airy version, maintaining ease of management.

The Diplomat RDL shown in the photos is available on the MoMoVaping website at the following link Diplomat RDL Style RTA 23mm Atomizer 316ss Vape Atomizer, along with its glass tanks and also the nano version with top fill.

I want to thank MoMoVaping for providing me with the Diplomat RDL, and the staff and the e-cigarette forum community for the space provided.