9mm is the width of N guage track. Because the description says it is narrow gauge, it might be HOn3; an HO scale train that runs on N gauge track. However, another statement in their description mentions 4mm, which would be extremely small. Z gauge track is 6.5mm, so if you’re really interested in bidding on this, I’d contact them for clarification.
It is British 4mm scale. That means 4mm equals 1 foot or 1:76 scale. But it is narrow guage 1:76 that runs on track which is 9mm wide. This is N-scale standard gauge track.
Z gauge track is 6.5mm gauge. N gauge is 9 mm. HO scale is 3.5mm=1 foot. OO scale is 4mm=1foot. Looks like OO scale narrow gauge, to run on N gauge track.
A 4mm scale model on 009 track means it is basically an OO scale (slightly bigger than HO, which is 3.5mm scale) narrowgauge model designed to run on N gauge track. It is closest to what in the US is called HOn30.
4mm is the scale aka '00". It’s a British scale close to H0 (H0 track is usually used for standard gauge as a compromise). This particular loco is narrow gauge, designed to run with 9mm narrow gauge track.
Don’t confuse Scale with Gauge, gauge is the distance between the rails regardless of scale.
One other note. Have you ever built a model from white metal like the one described? It’s really a pain in the rump. I bought a Durango maintanence of way set a few years back, and it was the hardest kit i’ve ever done. It has to be filed and sanded for hours to get a proper fit and it’s really hard to get the pieces to match together properly. You might want to change your mind about this one. I know I will never attempt another white metal kit if i can go with something else in it’s place…chuck
Could be British 2 mm scale, known as OOO scale, which was sort of a predecessor to N scale. From what I’ve read, it never had much commercial support and faded away in the 1960’s.
No your not being stupid its one of the peculiar to the UK scale gauge combinations
Its OO9 which means 4mm scale running on 9 mm gauge track, in other words its narrow gauge a scale 2’3" which is pretty close to the Talyllyn railway if memory serves.
For information on the real locomotive google Talyllyn Railway
If you are not familiar with white metal kits or not interested in narrow gauge don’t buy
It is however from a reputable UK manufacturer so should be a reasonable quality kit.
I cannot comment on the seller I dont use EBay I dont trust it
This is definitely a OO9 (OOn2 1/4) kit. It is 4mm / 1ft (1:76 scale) designed to run on 9mm guage track. This scale/guage is probably the most comon ng option in the UK and is used to represent many ng railways with guages between 2ft and 2ft6in (it actually scales out to 2ft 3in which is absolutely correct for this prototype).
The closest US equivalent is HOn30 - in that represents 30" guage, using HO scale and standard 9mm guage track. Assembled this engine will run on HOn30 track but may look slightly odd because in real life these are tiny locomotives compared even to say, the Maine 2ft railroads engines, but will appear about the same size due to the difference in scale.
The Meridian kits are OK if you are familiar with craftsman kits (this example is probably about 15 years old, but appears completely unmade), but the Ibertren N gauge chassis is a complete dog, but there is no real subsitute. The chassis are currently out of production and UK bidders will pay well over what would appear to be a sensible price for the chassis. Please be aware that the body kit is still available new for £21.99 from Parkside Dundas Models - one of the larger UK ng retailers.
Remember that Meridian and their ilk are cottage industries producing low numbers of craftsman kits that require some skill to make.