on saleDiplomat Magnum Fountain Pen - Lime Green

Product Code DP-D40908023

In Stock

out of stock

on saleDiplomat Magnum Fountain Pen - Lime Green

Product Code DP-D40908023

In Stock

out of stock


MSRP $33.00

Lime Green
Nib Guide

Not sure which size nib is best for you?

Try our Nib Nook tool to view and compare nib widths using our writing samples. Learn more ›

This lime green resin Magnum fountain pen is one of Diplomat’s most affordable offerings. The special no-slip lacquer gives the body a soft touch, and it has a black ergonomic grip section. It comes equipped with a smooth writing JoWo stainless steel nib, chrome trim, and fills via standard international cartridge/converter (both are included).

Note: The Diplomat Magnum is gradually transitioning from matte to polished nibs. What you receive may be different than what is pictured here.

Click to shop all compatible short or long standard international ink cartridges.

Fountain Pens

Whether or not the barrel of the pen is translucent, allowing you to see the ink and filling mechanism inside.

Body Material
Cap Type

How the cap is opened/closed from the barrel of the pen. Some common options include Snap-Cap, Screw-Cap, Magnetic Cap, or Capless (no cap).

Compatible inks & refills

Which ink this pen will accept. Choices include bottled ink and various styles of pre-filled ink cartridges.

Bottled Inks, Standard international long cartridges, Standard international short cartridges
Filling Mechanism

How the pen fills with ink. Click here to watch our video tutorial on common filling mechanisms.

Cartridge, Converter
Grip Material
Nib Size
Fine, Medium
Nib Color
Nib Material

Whether or not the cap fits securely onto the back of the barrel when open.


Whether or not the nib/tip can retract into the body of the pen (usually for click or twist-open style pens).

Diameter - Body
11.5mm (0.45in)
Diameter - Cap (without clip)
12.2mm (0.48in)
Diameter - Cap (with clip)
15.5mm (0.61in)
Diameter - Grip (mm)

Measured from the place most people choose to rest their fingers, which varies with each pen.

Length - Body

The measurement from the back end of the barrel to the tip of the nib.

123.9mm (4.88in)
Length - Cap
52mm (2.05in)
Length - Nib

The measured length of the visible portion of the nib when it is installed in the pen, from grip to tip.

17.1mm (0.67in)
Length - Overall (Closed)
133.3mm (5.25in)
Length - Overall (Posted)

When the cap of the pen is posted onto the back of the pen body, this is the measurement of the entire pen including the nib.

151.7mm (5.97in)
Weight - Body

If a converter is included with the pen, this weight is reflected in the total.

7g (0.25oz)
Weight - Cap
7g (0.25oz)
Weight - Overall (g)
Max Ink Capacity - Cartridge

The maximum volume of ink that can fit in the pen when using a cartridge.

Max Ink Capacity - Converter

The maximum volume of ink that can fit in the pen when using a converter.


Customer Reviews

Based on 15 reviews
Brandon P.
Its okay...

I was excited to buy this one after listening to the Goulet PenCast. For a $24 pen, this one kinda stinks. The nib doesn't write very well and has to be held at a very precise angle that is very wet. I used this one with the free Private Reserve Ink from the promo (I got DC Electric Blue and it is great) but I probably wont waste the ink in this pen. The other downside is that it weighs almost nothing. The pen cannot write at all under its own weight which is very disappointing for a German pen. Would definitely recommend LAMY Safari over this one at this price point. It does, however, come with a nice-sized Piston converter that pulls in the least air I have seen in most pens.

Matt H.

Of all the dozens of pens I have purchased in the past year, this is the only one I regret. The build construction is poor (sharp, unfinished seams around the ink window, between the barrel and grip, and on the barrel end cap), the weight and feel of the plastic is cheap, and the cutouts on the grip are uncomfortable (though this is largely personal preference). The nib itself seems to have a bit of a sweet spot. It writes very thick for a F and is pretty wet when you're right in that sweet spot, but it is scratchy and prone to skipping if you deviate very much at all. You can also get a tiny bit of flex out of the nib. I rotate through all my pens more or less equally, and this is the only one that I regularly skip. If you're OK with cartridges, I would go with a LAMY Safari or Pilot Metropolitan at this same price point. You can also get a Prefounte and add a converter, or 8-10 Jinhao Sharks for the same price if you want to use bottled ink. The only thing that saved this purchase for me was that it came with a full bottle of Private Reserve ink via special offer. I got Avocado, and I love it. If you look at this as buying a $15.00 pot of ink, and then getting the Magnum for $8, I feel a lot better about it (but I still wouldn't use it). Even then, if you're looking for a pen/ink combo you can get the 4.5 oz bottle of Noodler's for $1-2 less, and you get more ink with a vastly better quality pen in the Charlie it comes with.

ok starter pen

I bought the Diplomat Magnum in Lime Green because I could get free ink. The pen is a great color and has a smooth nib that writes well. The biggest drawback is the weight. Unfortunately, the Magnum is too lightweight and flimsy and is not comfortable to write with for long periods of time. With just a little more substance to the body this would be a favorite go to pen. It is a shame because it is a great color and has a really nice nib. I would not recommend the pen for the going rate of $23. If the pen were $10 less then it would be a great value.

Jim H.
Great 1st Fountain Pen

This pen writes beautifully. No hard starting, or skipping. Got the lime green one with an extra nib. It writes better than my ballpoints even on cheap office paper.

Audrey A.
Favorite starter pen

I recently bought a bunch of beginner-level pens, and this by far my favorite. The nib on this is fantastic, it has some springiness that I wasn't expecting. The pen itself is nothing special, just smooth plastic, but I didn't expect anything else. I'm still enormously pleased with his pen - I would have paid this price for the nib & feed alone. It's comfortable. (And I will, I have a Diplomat Traveller whose nib I don't like) This is what I use for writing longer text.

FAQs about Fountain Pens

How do I fill a fountain pen with ink? 8EDA1617-F73A-4DAF-8245-6D2BF4ABEB7B

It depends on the pen's filling mechanism, which you can find in the Technical Specs section above. 

Here's a quick definition of the most common filling mechanisms:

  • Cartridge - A small, disposable, sealed plastic reservoir that holds fountain pen ink. These come pre-filled with ink, and typically you just push to insert them into place and you'll be ready to write! Check out our quick guide here.
  • Converter - A detachable and refillable ink reservoir that allows you to use bottled ink in a cartridge-accepting pen. Typically you will install the converter into the grip section, dip the nib/feed into the ink, and twist or pull the converter knob to draw ink into the converter. Here's a video for how to fill a cartridge/converter pen using a LAMY pen as an example.
  • Eyedropper - A pen that utilizes the entire barrel as a reservoir for ink. Ink is directly filled into the barrel, allowing for a high ink capacity. Here's a video on how to do it!
  • Piston - A type of filling system that uses a retracting plunger inside a sealed tube to draw ink into a pen. They are typically either twist or push-operated. These pens cannot accept cartridges or a converter, and only fill from bottled ink.
  • Vacuum - A push-style piston that uses pressure to fill the large pen body with ink. They seal the ink chamber when closed, making it ideal for flying without risk of leaking. Check out our video on how to use a vac filler here.

Check out more info on these filling mechanisms including a video on how to fill each one on our blog.

How do I clean a fountain pen? 8EDA1617-F73A-4DAF-8245-6D2BF4ABEB7B

It depends on the filling mechanism, but it mostly comes down to flushing it out with water, and sometimes a little bit of Pen Flush if the ink is really stuck. 

It's a bit easier to show than to tell, so we've put together a few quick videos showing you the process:

How often do I need to clean my fountain pen? 8EDA1617-F73A-4DAF-8245-6D2BF4ABEB7B

We recommend a good cleaning every 2 weeks, and any time you change ink colors. 

Water will usually do the trick, but we recommend you use our Goulet Pen Flush if the ink has been left in the pen for a while and could have dried up, or when you’re switching ink colors.

My pen won’t write! What do I do? 8EDA1617-F73A-4DAF-8245-6D2BF4ABEB7B

First things first... make sure you have ink in the pen! Be sure that the ink cartridge or converter is seated properly in the pen, and that you aren't out of ink.

We always recommend you give your pen a good cleaning first, using our Goulet Pen Flush, or a drop of dish soap in some water. New pens often have some machining oil residue left in the feed, so a good cleaning often does the trick first.

If that still doesn't work, try priming the feed. This consists of either dipping your pen nib and feed in ink, or forcing ink from the converter down into the feed. 

If it’s still not working after that, please reach out to us so we can help! 

What's your return policy? 8EDA1617-F73A-4DAF-8245-6D2BF4ABEB7B

You can submit a return request within 30 days of your order date. You can read all our Return Policies here.

To initiate a return, please submit a request at the Return Portal. Our Customer Care team might reach out to you for more information.

Please note we are unable to accept a return of any Namiki or Sailor Bespoke fountain pen for any reason once it has been used with ink. Please thoroughly inspect and dry test the pen before use.