Pilot CON-40 Ink Converter Guide

Pilot CON-40 Ink Converter 60 mm piston converter — _{Pilot CON-40 Ink Converter, a 60 mm rotating-piston converter for compatible Pilot and Namiki fountain pens.}

Looking for the squeeze-style version? See the Pilot CON-B Squeeze Ink Converter guide. For the larger push-button version, see the Pilot CON-70 Ink Converter guide.

Not sure this is the right converter? Use the Pen Refill Finder to compare converter, cartridge, refill size, format, and compatibility.

Buy the Pilot CON-40 Ink Converter

The Pilot CON-40 is the compact rotating-piston converter used across many Pilot and Namiki cartridge/converter fountain pens.

Quick Specs

Specification	Details
Common Name	Pilot CON-40 Ink Converter
Other Common Names	Pilot CON-40 Converter, Pilot CON-40 Piston Converter
Product Type	Fountain pen ink converter
Filling Type	Rotating / twist-piston converter
Length	60 mm
Maximum Diameter	Approx. 7.2 mm
Official Ink Capacity	Approx. 0.4 mL
Ink Source	Bottled fountain pen ink
Cartridge Alternative	Pilot Fountain Pen Ink Cartridge
Compatible Brands	Pilot, Namiki
Key Similar Converters	Pilot CON-B, Pilot CON-70
Internal Agitators	Yes
Proprietary or Standard	Proprietary Pilot/Namiki converter
Reusable?	Yes
Ink Compatibility	Use fountain pen-safe bottled ink only

Pilot CON-40 Ink Converter Overview

The Pilot CON-40 Ink Converter is a reusable rotating-piston fountain pen converter designed for compatible Pilot and Namiki cartridge/converter fountain pens.

At 60 mm long, it is compact enough to fit a broad range of Pilot pens while still providing the convenience of bottled fountain pen ink.

The CON-40 uses a threaded piston mechanism. Rotating the rear knob moves the piston through the reservoir, creating suction that draws ink through the nib and feed.

Pilot officially lists its ink capacity at approximately 0.4 mL.

What Are the Metal Balls Inside the Pilot CON-40?

The Pilot CON-40 contains small metal agitators inside the clear reservoir.

These move around as the pen is handled and help break surface tension and air bubbles inside the converter. That can help ink move more freely toward the feed rather than remaining suspended against the walls of the reservoir.

The small metal pieces are therefore intentional parts of the converter and are not loose or broken components.

Why Choose the Pilot CON-40 Ink Converter?

The CON-40 is a good choice when you want a compact, conventional piston converter for a compatible Pilot or Namiki fountain pen.

Benefits include:

Compact 60 mm length
Rotating piston mechanism
Transparent reservoir
Internal ink agitators
Broad Pilot/Namiki compatibility
Reusable bottled-ink filling
More visible ink level than the CON-B squeeze converter

Its primary tradeoff is ink capacity. The larger CON-70 holds considerably more ink, but the CON-40 fits pens that do not have enough barrel space for the longer converter.

Pilot CON-40 vs CON-B vs CON-70

Converter	Mechanism	Length	Approx. Capacity	Best Use
Pilot CON-B	Squeeze	58 mm	~0.6 mL	Simple compact converter
Pilot CON-40	Twist piston	60 mm	0.4 mL official capacity	Broad compatibility and visible piston filling
Pilot CON-70 / CON-70N	Push button	80 mm	1.1 mL	High-capacity filling in larger pens

The CON-40 is the middle ground in physical size, although its official ink capacity is smaller than both the CON-B and CON-70.

Pilot CON-40 Compatibility Notes

Pilot states that the CON-40 is intended for Pilot cartridge fountain pens and desk pens, with certain exceptions.

Because it is only 60 mm long, it fits a much broader range of Pilot pens than the 80 mm CON-70.

Common compatible models may include:

Pilot Metropolitan
Pilot Prera
Pilot Kakuno
Pilot Explorer
Pilot Vanishing Point / Capless
Pilot Falcon
Many Pilot Custom-series cartridge/converter pens
Many Namiki cartridge/converter fountain pens

Model-specific compatibility should still be confirmed.

Pilot CON-40 vs Pilot Ink Cartridge

Option	Reusable?	Ink Source	Best For
Pilot CON-40	Yes	Bottled fountain pen ink	More ink choices and reusable filling
Pilot Fountain Pen Ink Cartridge	No	Pre-filled ink	Simplicity, travel, and greater disposable ink capacity

Pilot cartridges are faster and cleaner to install. The CON-40 provides access to bottled inks from Pilot and other fountain pen ink brands.

How to Fill the Pilot CON-40 Ink Converter

Install the CON-40 securely into the fountain pen section.
Rotate the piston knob so the piston moves toward the front of the converter.
Dip the nib and feed fully into bottled fountain pen ink.
Rotate the knob in the opposite direction to draw ink through the nib and feed.
Allow the converter to fill.
Remove the nib from the bottle.
Wipe away excess ink.
Reassemble the pen.

For a fuller fill, the process can sometimes be repeated after expelling air back into the bottle.

Use only bottled fountain pen-safe ink.

Compatible Pens

The Pilot CON-40 works with many Pilot and Namiki cartridge/converter fountain pens.

Common examples include:

Pilot Metropolitan
Pilot Prera
Pilot Kakuno
Pilot Explorer
Pilot Vanishing Point / Capless
Pilot Falcon
Select Pilot Custom-series pens
Many Namiki cartridge/converter fountain pens

Not every Pilot fountain pen uses a converter. Confirm your exact model before ordering.

Compatible Brands

The Pilot CON-40 is designed primarily for:

Pilot
Namiki

It uses Pilot’s proprietary connection and is not a standard international converter.

Alternative Cartridges and Converter Options

Common alternatives include:

Pilot CON-B Squeeze Ink Converter — compact squeeze-style converter
Pilot CON-70 Ink Converter — high-capacity converter for pens with enough barrel space
Pilot Fountain Pen Ink Cartridge — disposable cartridge option
Bottled fountain pen ink — used with the converter

Converter Family

The Pilot CON-40 belongs to Pilot’s proprietary fountain pen converter family.

It is the compact rotating-piston converter, sitting between the squeeze-style CON-B and the much larger push-button CON-70/CON-70N in overall size.

The CON-40 is especially useful in pens where the CON-70 is physically too long.

How to Identify the Pilot CON-40 Ink Converter

Key identification points include:

60 mm overall length
Clear plastic reservoir
Black rotating piston knob
Internal metal agitators
Proprietary Pilot connection
Reusable with bottled fountain pen ink
Shorter than the CON-70
Different from the metal-covered CON-B squeeze converter

The clear reservoir and visible metal agitators make the CON-40 easy to distinguish from Pilot’s other common converters.

Frequently Asked Questions

What is the Pilot CON-40 Ink Converter?

The Pilot CON-40 is a 60 mm reusable rotating-piston converter for many Pilot and Namiki cartridge/converter fountain pens.

How long is the Pilot CON-40?

Pilot officially lists the CON-40 at 60 mm long.

How much ink does the Pilot CON-40 hold?

Pilot officially lists its ink capacity at approximately 0.4 mL.

What are the metal balls inside the CON-40?

They are agitators designed to help break surface tension and air bubbles so ink can move more freely within the reservoir.

Is the Pilot CON-40 reusable?

Yes.

Does the Pilot CON-40 fit the Metropolitan?

Yes. The Metropolitan is commonly used with the CON-40, although some Metropolitan pens have also been supplied with the CON-B.

Does the Pilot CON-40 fit the Vanishing Point?

The CON-40 is commonly used with compatible Pilot Vanishing Point / Capless fountain pens.

What is the difference between the CON-40 and CON-B?

The CON-40 uses a twist-piston mechanism and has a transparent reservoir. The CON-B uses a squeeze sac.

What is the difference between the CON-40 and CON-70?

The CON-70 is much longer and holds substantially more ink. The CON-40 is shorter and fits more compact Pilot pens.

Is the Pilot CON-40 standard international?

No. It uses Pilot’s proprietary converter connection.

What ink can I use with the Pilot CON-40?

Use bottled fountain pen-safe ink only.

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