Fisher Space Pen 400BTN – the brand’s first and most popular model

The Fisher Space Pen 400BTN is the brand’s first model and remains the most sought-after to this day. The barrel is made of brass coated with titanium nitride – one of the hardest and most abrasion-resistant coatings used in medicine and the space industry. 🚀

The golden colour is not paint – it is the natural result of applying titanium nitride to the brass.

Space-proven technology

The cartridge operates using pressurised nitrogen – a small metal cylinder pushes the thixotropic ink, which is solid when at rest but liquefies when writing. The ink is hermetically sealed.

The pen writes reliably at:

temperatures ranging from -34°C to +120°C
underwater and in zero gravity
at any angle, including upside down
3 times longer than standard ink

The refill tip is a tungsten carbide ball. The pen does not skip or leak.

Design and convenience

Its compact size makes it easy to carry in a wallet or organiser. The clip secures the pen to the edge of a pocket or rucksack.

Length when extended: 13.6 cm
Length when retracted: 9.6 cm
Barrel: brass with a titanium nitride coating
Refill: SPR4 – black ink, medium tip
Compatible with all Fisher PR refills
Comes in a cardboard gift box

Every Fisher Space Pen is precision-assembled, hand-tested and comes with a lifetime guarantee against manufacturing defects.

A gift with history and character

Paul S. Fisher developed this pen entirely with his own funds – around 1 million US dollars – without any funding from NASA. 🛸

In 1967, following rigorous testing, NASA equipped the astronauts on the Apollo mission with these pens. In February 1969, the Soviet Union also purchased 100 pens and 1,000 refills for the Soyuz missions. To this day, American astronauts and Russian cosmonauts continue to use them in orbit.

Prior to this, NASA had used mechanical pencils – 34 in total at a cost of $4,382.50, or $128.89 each – which caused public outcry and prompted the agency to seek a better solution.

The Fisher Space Pen 400BTN is a practical and prestigious gift for men – suitable for doctors, lawyers, military personnel, police officers, business leaders, teachers and school leavers. It doesn’t freeze in winter or run in summer.

Specifications	Price
Brand	Fisher Space Pen
Model	400BTN
Length when extended	13.6 cm
Length when retracted	9.6 cm
Body material	Brass with titanium nitride coating
Colour	Gold (natural colour of titanium nitride)
Refill	SPR4 – black ink, medium nib
Compatibility	All Fisher PR refills
Tip	Tungsten carbide tip
Operating temperature	-34°C to +120°C
Warranty	Lifetime against manufacturing defects
Contents of the set	Pen and cardboard gift box

Frequently asked questions

What is special about the titanium nitride coating on the Fisher Space Pen 400BTN?

Titanium nitride is an extremely hard and abrasion-resistant coating. It is used in medicine to coat implants and in the aerospace industry to enhance the durability of certain components. Applied to the pen’s brass barrel, it provides lasting protection against scratches and wear. The golden colour is a natural result of the coating itself – it is not paint or varnish. This is precisely why the Fisher Space Pen 400BTN stands out visually and lasts much longer than pens with conventional coatings.

How does the Fisher Space Pen’s cartridge work, and why is it different from standard ones?

The Fisher Space Pen’s cartridge operates using pressurised nitrogen. A small metal cylinder inside the cartridge pushes the thixotropic ink towards the nib. Thixotropic ink is solid when at rest and only liquefies when writing – this means the pen does not leak or skip. The ink is hermetically sealed, allowing the pen to write at any angle, underwater, in zero gravity and at temperatures ranging from -34°C to +120°C. The writing tip is a tungsten carbide ball – a hard and durable material. The SPR4 refill contains medium-thickness black ink and writes up to three times longer than standard ink.

Has the Fisher Space Pen been used in actual space missions?

Yes. Paul S. Fisher developed the pen entirely with private funds – around 1 million US dollars – without any funding from NASA. Following rigorous testing carried out up to 1967, NASA equipped the astronauts on the Apollo mission with these pens. Previously, the agency had used mechanical pencils, purchased at a cost of $128.89 each, which had caused public outcry. Fisher offered the pens at a significantly lower price – around $6 each. In February 1969, the Soviet Union also purchased 100 Fisher pens and 1,000 refills for the Soyuz missions. To this day, these pens are still used by astronauts and cosmonauts.

What warranty is provided for the Fisher Space Pen 400BTN?

Every Fisher Space Pen is precision-assembled and hand-tested before leaving the production line. The product comes with a lifetime guarantee against all manufacturing defects. This means that if a defect in materials or workmanship is found, the manufacturer will be responsible for repair or replacement. The warranty is valid for the entire lifetime of the product and is a mark of confidence in the quality of the Fisher Space Pen brand.

Who would the Fisher Space Pen 400BTN make a suitable gift for?

The Fisher Space Pen 400BTN is a practical and prestigious gift for a wide range of people. It is suitable for doctors, lawyers, military personnel, police officers, teachers, business leaders, politicians, tradespeople and school leavers. The pen does not freeze in winter or leak in summer, making it convenient to carry in the car, a handbag or a rucksack. Its history and the technology behind it also make it an interesting topic of conversation. Its compact size and the clip for attaching it to a pocket or rucksack add to its practicality. It comes in a cardboard gift box, ready to give.

What refills does the Fisher Space Pen 400BTN work with?

The pen comes with an SPR4 refill – black ink with a medium line width. In addition, it is compatible with all Fisher Space Pen PR refills. This allows you to choose different ink colours or line widths when replacing the refill. Fisher refills are widely available and easy to find as spare parts.

What are the dimensions of the Fisher Space Pen 400BTN and how compact is it?

When retracted, the pen is 9.6 cm long – small enough to fit in a wallet, organiser or small pocket. When extended to its writing position, it measures 13.6 cm, providing a comfortable grip when writing. The clip allows it to be attached to the edge of a pocket or rucksack. Its small size does not compromise its functionality – the pen performs perfectly in all conditions.