An Introduction to TWSBI Fountain Pens

An Introduction to TWSBI Fountain Pens

TWSBI fountain pens are one of our favorite fountain pens and many people don't know this about Yoseka, but they are actually the very first fountain pens we added. Back in 2017, when Neil and I were just getting started doing pop-ups, Yoseka was a very different shop! The store pretty much existed out of our car and the wooden crates that we would load up with stationery each week and haul to whichever location where we were popping up. For the first six months, Yoseka was a different experience each time you visited us because we were experimenting and learning lots about what works well and who we were as a shop. Somewhere along the way, we decided to give fountain pens a try. Neil and I were both fountain pen newbies, but of course we had to start with TWSBI because we had heard great things about this fountain pen company with Taiwanese roots. 

January 2018: Neil fills one of our first TWSBI fountain pens at Diviera Drive's holiday pop-up market


Fast forward to five years and many TWSBI pens later, we know a lot more about fountain pens now and for many reasons, TWSBI fountain pens are a favorite and one of the pens I personally recommend most often when someone at the store asks me what pen they should get. 

TWSBI fountain pens first emerged in 2009. Their father company, Ta Shin Precision, was an OEM manufacturer for other global brands with over 50 years of experience producing goods with plastics and other materials. What is an OEM manufacturer though? Fear not! I had to look this up myself. Apparently OEM manufacturers produce things for other brands. This makes sense and meant that Ta Shin Precision had a lot of expertise in making goods and so, in 2009, they set out to make their own products and TWSBI fountain pens were born. Fountain pen lovers rejoice :) 

The name TWSBI (pronounced Twiz-be*) trips people up! We often get visitors to the shop lean in and whisper to us if we have those "T-W-S-B-I" pens. The story behind the name requires a little bit of explanation (just like the story behind Yoseka's name and logo so we can definitely relate!) In Chinese, TWSBI is "San Wen Tong," which translates to Hall of Three Cultures and evokes the historical Hall of Three Rare Treasures created by Emperor Qianlong to house masterpieces of Chinese calligraphy in the Qing dynasty. TWS takes the initials of San Wen Tong and reverses them and the final BI actually just means pen in Chinese. And there you have it! The explanation behind TWSBI's brand name. 

Now that we've talked a little about TWSBI as a company, we can go into their fountain pens. TWSBI offers a few different models of fountain pens and we get a lot of questions about the differences between the different models. The important thing to note about TWSBI fountain pens in general is that they were designed to be a very well-constructed fountain pen at an affordable price point so you probably won't see TWSBI releasing any pens with a gold nib, or decorative maki-e, ornate raden or anything like that. TWSBI excels at producing really practical, easy-to-fill and easy-to-maintain fountain pens that write very well too. They're low maintenance since most of them hold so much ink that they'll never dry out and they don't require any separate purchases like a separate converter or additional cartridges. A bottle of ink and you're good to go for quite a while with your TWSBI! Another thing that TWSBI is known for is their limited edition releases. Every couple of months, TWSBI releases one of their established models in a new color, sometimes with special details, which is why you'll rarely find someone with just one TWSBI--they are highly collectible and it's a lot of fun for us to follow all the colors that they release.


Top: TWSBI Diamond 580, Bottom: TWSBI ECO

TWSBI Diamond 580

This model is how it all began for TWSBI. Back in 2009 when TWSBI released its first fountain pen, it was a variation of the Diamond 580, which has since seen improvements in its durability. The Diamond 580 is a piston filling pen, as are most TWSBI pens. It comes with a #5 nib and unlike the ECO, which is another very popular model of TWSBI pen, you can screw off the nib and grip section and easily replace it with another nib size. The resin on the Diamond 580 is durable and scratch resistant, which is another reason why this model is slightly more expensive than the others. 

Cap Finials, Top: TWSBI Diamond 580, Bottom: TWSBI ECO


The ECO in the TWSBI ECO stands for "economical" because it is at a lower price point than the already-affordable Diamond 580. With some substitutions such as a smaller nib, a different resin and a nib unit that is easily removable with threaded parts, the ECO model was introduced in 2015! The ECO is also a piston-filler with a screw cap and overall, a similar look to that of the Diamond 580, but with a #4 nib, it writes slightly differently from the Diamond 580. Although it is less expensive, I consider the ECO to be just as great as a fountain pen as the Diamond 580! 


The ECO-T is actually extremely similar to the ECO and you can't easily spot the differences since they are so subtle. The body of the ECO-T is made of the same resin as the ECO and it comes with the same nib, but the grip of the ECO-T is triangular as opposed to the rounded grip section of the ECO. This will appeal to those who enjoy a pen with a triangular grip that comes with 3 facets such as the LAMY Safari. Some say it is easier for a newcomer to the fountain pen world to use a triangular grip, but it's a personal preference as are many things when it comes to stationery. 

Top: TWSBI Diamond 580, Bottom: TWSBI Diamond Mini

TWSBI Diamond Mini

A smaller version of the Diamond 580, the Diamond Mini is a piston-filling pen with a #4 nib. The back of the Diamond Mini is threaded so you can post the cap onto the back of the pen by twisting it into place, making the smaller barrel an easier size to hold and write with. Like the Diamond 580, the nib and grip section are removable since they twist off easily, and spares are available as well. 


The TWSBI Vac700R utilizes the largest nib of all TWSBI pens--the #6 nib. It has a screw cap and actually has the largest ink capacity of all the TWSBI pens. Like the Diamond 580, the barrel and cap of the Vac700R are made of a durable scratch-resistant resin. The nib and grip unit of the Vac700R are removable as one piece and can be replaced with a nib of another size. The most notable difference between the Vac700R and the other models of TWSBI pens is its filling mechanism. As the name suggests, the Vac700R is a vacuum filling pen with a built in ink shut off valve that you can screw down to close off ink supply and prevent burping/spillage in transit.

TWSBI Vac Mini

The TWSBI Vac Mini is a smaller pocket-sized version of the Vac700R that comes with #4 nib. Despite its smaller size, it still has quite an impressive ink capacity due to its vacuum filling mechanism. The nib and grip unit of the Vac Mini are removable and can be replaced with a nib of another size. Like the TWSBI Diamond Mini, the Vac Mini has threading on the back so you have the option of screwing to post the cap. 


The TWSBI Go is probably the model that is the most visibly different from all the other TWSBI models. For writing, it actually writes exactly the same as the ECO, Mini, Vac Mini and Swipe since it utilizes the same #4 size nib, but it is more affordable due to substitutions in a few areas: first, instead of a screw cap, it comes with a snap cap; second, the resin material that the pen is made of is thinner and less opaque; third, the piston filling mechanism is reliant on a spring instead of the typical screw; and fourth, there is no clip but there is a roll stopper, a small protrusion on the cap that will prevent the pen from rolling off a desk or table. All of these adjustments to the engineering of the TWSBI Go allow it to be the most affordable TWSBI option and in my opinion, one of the best values of any fountain pen!


The TWSBI Swipe is the newest of all the TWSBI models and is TWSBI's first cartridge/converter fountain pen, making it stand out from all the aforementioned models in this blogpost. The TWSBI Swipe comes with a #4 nib and a snap cap. Also included with purchase are two of the largest international standard converters we've ever seen, a black ink cartridge and an optional spring to help hold the cartridge in place. 

 Here's a little chart to summarize take aways on these TWSBI models:

TWSBI Model JoWo Nib  Available Nib Options Filling Mechanism Cap (Screw/Snap) Replaceable Nib Available
Diamond 580 #5 EF, F, M, B, 1.1 Screw Piston Screw Yes
EF, F, M, B, 1.1
Screw Piston Screw No
Diamond Mini #4
EF, F, M, B, 1.1
Screw Piston Screw Yes
Vac700R #6
EF, F, M, B, 1.1
Vacuum Screw Yes

Vac Mini

EF, F, M, B, 1.1
Vacuum Screw Yes
Go #4 EF, F, M Spring Piston Snap No
Swipe #4
EF, F, M, B, 1.1



Snap No


TWSBI Limited/Special Editions

TWSBI Limited Edition pens from left to right: ECO-T Mint Blue, ECO Transparent Orange, Diamond 580 Smoke RoseGold, ECO White RoseGold, Vac700R Iris, Diamond Mini White RoseGold, and ECO Jade 


Now that you understand some more about TWSBI pens and the possible different models that you can choose from, something else important to note about TWSBI is that they regularly release limited edition colors. For the most part, these are still demonstrators, with either a colored cap, piston or grip section. TWSBI has released limited edition colors in their Diamond 580s, ECOs, ECO-Ts, Diamond Minis, and SWIPEs. These colors are usually around for one or two years, or sometimes even longer, but then they go out of production and become harder to find. 

Hope this blogpost helps you understand TWSBI pens a little bit better. Look out for another post soon with a nib and line comparison of the three different TWSBI nibs available--the #4, 5 and 6. You can check out our TWSBI fountain pens here:



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