Strap for Railroad 46 Chrono Stainless Steel / Black / Bracelet

The lug width of the H40616135 is 22mm. This dimension was chosen by Hamilton to ensure optimal proportions between the 46mm case and the strap, avoiding visual disproportion on a chronograph of this scale. Lug width is measured by placing a ruler on the inside of the case, between the inner edges of the two lugs, without including the thickness of the lugs themselves.

The recommended choice is Tuscan vegetable-tanned leather in Marrone Testa di Moro (deep brown), which creates a textural dialogue with the steel case and develops natural patina over time. Equally valid alternatives include alligator for superior durability and natural grain texture, or rubber for more dynamic wear. NATO fabric straps offer aesthetic versatility and quick-change practicality whilst maintaining the austere original railway aesthetic.

Strap changes are made via the lugs: with the watch upside down, locate the two small metal pins protruding on the sides of the case. Using a small spring bar tool or flat screwdriver, gently push the pin in the direction opposite to the spring spiral (usually toward the case centre) until the old strap releases. Align the new strap holes with the pins and reinsert them using the same method in reverse. If unfamiliar with the procedure, consult a specialist atelier to avoid case damage.

A strap is compatible with the H40616135 if it has a 22mm lug width. This means the distance between the inner holes of the strap must correspond to 22mm. Ideal thickness should not fall below 1.3mm to ensure longevity and correct proportions on a chronograph of this scale. Milano Straps 22mm straps are certified compatible with the H40616135 and available in leather, rubber and fabric.

Leather strap durability depends on tanning method and usage patterns. A Tuscan vegetable-tanned leather strap of 1.4–1.5mm thickness typically lasts 4–6 years with daily wear, developing natural patina throughout. Alligator guarantees 7–10 years or more owing to superior structural density. Durability increases significantly if the strap is removed after wear and stored in controlled humidity conditions. Periodic maintenance with specialised creams extends useful life by 20–30%.