Hey guys!
I wasn't sure if this has been done before, but I mostly did this for myself and figured I might as well share it. The questions regarding the differences come up a lot, and it is a little difficult to decipher on the site when you are new to REOs. Please do let me know if I made a mistake somewhere, as I gathered this information from quite a few different sources, and did not take these measurements myself, nor have I observed most of these first hand - I only have an RM3 and RM4 at this time.
Also note that the RM6 is on this chart. It is not on the Reo site... yet

Most of what I gathered on that is from smiddleton's RM6 review post, and what I know about the Stillare.
Atomizer | Dimensions
(W x H) | Coils | Air | Construction
(Cap/Deck/Posts) | Options | Fitment |
RM2
Triangle by Empire Mods, modded to bottom feed | 14.5mm x 25mm (inludes 510 connector height) | Single | Single 3/64’’ air hole = aprox. 1.2mm.
(The Brass Cap is easily bored to make larger air hole) | Threaded Brass Cap, Ceramic Deck, Brass Nickle plated Posts use phillips screws | Brass or Nickel Finish.
Standard is Milled for standard catch cups
LP is not milled for LP catch cups | Fits all Reos, but choose LP for LP Mods for best look |
RM3
A-6 modded to bottom feed | 14.2mm x 24.4mm (includes 510 connector height) | Single OR Dual | Single OR Dual
3/64’’ air hole(s)
| Stainless Cap, Stainless Deck, Brass Nickle plated posts use phillips screws, Cap to Deck Double O-ring Fit. | Stainless Finish only. Choose Single air hole cap OR Dual air hole cap.
| Fits all Metal Reos. Fits Wood Reos after 2014 |
RM4
Atomic clone modded to bottom feed | 19mm x 24.3mm (not including 510 connector height) | Single AND
Dual | Single AND dual 3mm, 2mm, or1.5mm | Full Stainless. Top Half of Cap Threaded for AFC, Cap to Deck single O-ring fit, uses allen screws | Stainless Finish Only. | Fits only LP versions |
RM5
Double Cross modded to bottom feed | 22mm x 25mm
(not including 510 connector height) | Dual | Two horizontal slots, adjustable vertical opening via threaded control | Full Stainless. Posts ideal for flat ribbon wire, uses allen screws. Top Cap to Deck Double O-ring fit | Stainless / Gold
or
Stainless / Charcoal Finish | Fits only LP versions |
RM6
Stillare clone modded to bottom feed | 22mm x 33mm (includes 510 connection height) | Dual | Two horizontal slots, adjustable horizontal opening via sliding two piece cap | Full Stainless. Posts are gold plated stainless, uses phillips screws. Single O-ring Cap to Deck, Single O-ring on two piece Cap for AFC | Stainless Finish Only. | Fits only LP versions |
View attachment 371412
Cheers, folks!
- Bboy