EnsO Puma Pocket Ultim Review: A Tiny Eyedropper-Ready Pocket Pen

Introduction

The EnsO Puma Pocket Ultim is the latest release from EnsO, following the Puma Primary Manipulation reviewed a little over a month ago. It is a limited edition of 150 units, and EnsO limited editions tend to sell out, so timing matters if this one interests you. At $95 it is reasonably priced for a pen this unusual, and this review covers the design, materials, and writing performance to help you decide whether to act quickly.

Design and Materials

The name Puma comes from the Italian word for feather, a nod to the very first fountain pens made from feathers. The Ultim part refers to Ultem, an engineered polyethylene plastic commonly used in structural applications such as aerospace components and medical devices. It is stronger than acrylic and other resins, and it is chemically and temperature resistant.

The most striking trait is the distinct transparent amber color. Because the material is translucent, you can see the outline of the nib through the cap and barrel, and the black lacquered nib version looks especially mysterious through the plastic.

The exterior is not completely smooth. Very small tooling grooves run across the entire pen, adding a minute amount of texture. That texture helps you keep a grip on such a small device, and it also means the material does not really lend itself to engraving. There is no exterior branding on the pen at all, which is normally a small annoyance, but with this material it is easy to forgive.

The pen has a bullet-shaped profile with a rounded cap top. It is clipless, and the cap twists off in just over a single rotation. The barrel is tiny, only about an inch and a quarter, with a medium-sized step down to the posting threads and a rounded end. Typically twist-to-post mechanisms look awkward when not in use, but here the threads are hidden in plain sight, and they barely register.

Everyday Use and Comfort

This is a pen designed to be used posted. Unposted, the short barrel nestles into your palm for quick notes, but anything longer than a jot becomes uncomfortable. Posted, the pen reaches the length of most standard pens, and the rounded barrel end helps the cap align easily without fidgeting to find the right position.

The section begins with a rounded flare and angles up to the cap threads. It is not slippery at all, and the subtle grooves genuinely help maintain grip. The nib is a number six Jowo stainless steel unit: the black lacquered version is available in fine, medium, and broad, the polished stainless steel version comes in fine or medium at an additional cost, and there is also an option for a fine titanium nib.

Filling Options

The pen runs on a standard international short cartridge or can be converted to eyedropper filling. The eyedropper story is where the design shines. There is an O-ring at the base of the section, and the threads that affix the section to the barrel are longer than normal. Together, those two features significantly reduce the risk of leaking. Adding a small amount of silicone grease to the threads gives a third layer of ink protection.

Converted to eyedropper, the pen holds a decent ink capacity, and watching ink slosh around the translucent amber barrel is half the appeal. Ink flow also started surprisingly quickly after filling, within 15 or 20 seconds, rather than the longer priming time a cartridge in a brand new pen often needs.

Writing Performance

The medium stainless steel nib laid down a vibrant line, tested with Three Oysters Chili Red, Diamine Poppy Red, and Stilo and Stile Roman Centurion Red, all of which pair well with the amber body. The nib has a fair amount of feedback, leaning feedbacky rather than smooth, and there is not much line variation. Ink flow on the medium nib runs on the lower side.

Reverse writing is not very sharp and lays down an extra-fine line. For faster writing, the feed keeps up just fine, which is reassuring in a pen this small.

Buying Advice

The EnsO Puma Pocket Ultim is available only through the EnsO website at $95. Between the translucent amber Ultem construction, the hidden twist-to-post threads, and the well-executed eyedropper conversion, it earns its price for a pen of this size. With only 150 units in the edition and EnsO limited editions tending to sell out, sooner rather than later is the sensible approach if it appeals to you.

Conclusion

The Puma Pocket Ultim is an interesting pocket pen that holds a decent amount of ink and looks neat doing it. It rewards posted use, grips well thanks to its grooved texture, and the eyedropper design is genuinely thoughtful. If you want a compact pen with real filling capacity and a distinctive look, this limited edition is worth chasing before it disappears.