Panerai Radiomir vs. Radiomir 1940 Case Comparison

The Officine Panerai brand as we know it today has only been around since the 1990s, yet the company has a history that stretches back to 1860 when Giovanni Panerai established a watchmaker’s shop in Florence, Italy. Panerai then began supplying diving watches to the Royal Italian Navy just before World War II (the precursors to the Panerai Radiomir) and continued its relationship with the Italian government until the 1980s. In 1993, Panerai became available to the public for the first time and a few years later, Richemont (then known as the Vendome Group) purchased the brand and grew it to become the popular luxury watch brand it is today.

The current Panerai catalog is largely composed of watch models inspired by those developed in the 1930s, 1940s, and 1950s for Italian combat divers, including the Radiomir collection. And among the Panerai Radiomir collection, there are two main case styles: the Radiomir and the Radiomir 1940. The overall look of these two may be quite similar at a glance, yet if we look closer we see a handful of distinct differences. Let’s get into the Panerai Radiomir vs. Radiomir 1940 case comparison to highlight the origins, similarities, and differences.

The Origins of the Panerai Radiomir

By the early 20th Century, Panerai had already been supplying the Royal Italian Navy (known as the Regia Marina) with high-precision instruments. For better visibility in dark environments, Panerai patented a radium-based self-luminous material called Radiomir in 1916 to paint onto the military-grade instruments.

The Regia Marina put out a call for watches that could accompany its fleet of frogmen and by 1936, Panerai supplied ten prototypes for the navy’s consideration. The watches featured massive 47mm cushion-shaped cases built by Rolex (remember, Rolex was a pioneer in waterproof watches, having introduced the Oyster in 1926), hand-would movements (signed Rolex), and dials painted with self-luminous radium-based paint. The cases included welded wire lugs to attach the straps and an oversized flared winding crown for easy access, even while wearing gloves.

According to Panerai, in 1940 (although some Panerai scholars dispute this and claim that it was actually in the 1950s), the Radiomir’s case design evolved for even better performance. For improved resistance to tension and to prevent the lugs from detaching from the case under extreme pressure or impact, the case and lugs were built out of the same block of steel rather than welding lugs onto the case. This resulted in much thicker lugs than the previous wire ones that were fitted to the original Panerai Radiomir. Furthermore, the conical crown was replaced with a cylindrical one, presumably to reduce the risk of it getting caught on things or knocked off if accidentally hit.

Case Study: Panerai Radiomir vs. Radiomir 1940

In 1997, Panerai, which was already under the Richemont umbrella, introduced the limited edition PAM 21 (61 examples) with a design based on the 1930’s Panerai prototype watches, complete with a 47mm case, wire lugs, and conical winding crown. The watch was called Radiomir – referencing the patented luminous material from 1916 – and it paved the way for the design blueprint of all future Panerai Radiomir watches.

In 2012, Panerai introduced the Radiomir 1940 models in the form of the red gold PAM 398 and stainless steel PAM 399. While also 47mm in diameter, the case designs were based upon the evolved vintage Panerai watches with thick lugs and a cylindrical crown. This pair of limited edition (100 pieces each) Panerai watches kick-started the Radiomir 1940 family, which has since welcomed a wide assortment of other references.

The biggest differences between the Radiomir and Radiomir 1940 cases are the shape of the lugs and winding crown. Furthermore, the bezel execution is also slightly different where the former has a thinner rounded bezel and the latter has a flatter and thicker bezel. Finally, the corners of the cushion-shaped case of the Radiomir 1940 are slightly sharper and more pronounced while the corners of the Radiomir are rounder and softer.

• Panerai Radiomir: wire lugs, large flared crown, thinner bezel, rounded corners


• Panerai Radiomir 1940: thick fixed lugs, flat cylindrical crown, thicker bezel, sharper corners

Both Radiomir and Radiomir 1940 cases are available in a variety of sizes, typically 42mm, 45mm, and 47mm, although a few other sizes (always 40mm or larger) are sometimes used for special edition models.

Regardless of the size, the Radiomir is dressier in style than the Radiomir 1940 thanks to the thinner lugs and bezel, vintage-style winding crown, and curvier silhouette. The Radiomir 1940’s thick lugs, squat crown, sharper corners, and broader bezel lends the watch a sportier feel – some have even equated it to the Panerai Luminor watch but without the bulky bridge crown protector.

It’s also worth noting that Panerai no longer officially segments the Radiomir and the Radiomir 1940 case styles on its website. Instead, the brand features all of them in the same section under the Radiomir banner. Therefore it’s even more important for you to understand the differences between the Panerai Radiomir and Radiomir 1940 cases to make the right choice when picking out your future Panerai watch.