Omega · Speedmaster Broad Arrow

Strap for Speedmaster Broad Arrow Red Gold / Enamel

Takes 20 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.

Lug width20 mm
Case diameter42 mm
Reference3654.20.31
FamilySpeedmaster Broad Arrow
MovementOmega caliber 3320 Hours, Minutes, Small Seconds | Date | Chronograph, Column wheel
CaseRed Gold

Recommended spring bar

Spring bars Omega 20mm — 1.8mm diameter

Technical match for lug width and diameter · lug 20 mm · Ø 1.8 mm

All Omega spring barsOpen →

Straps for the Speedmaster Broad Arrow 3654.20.31

Selected for the 20 mm lug width · workshop selection

All 20 mm straps →

The Speedmaster Broad Arrow 3654.20.31, seen from the bench

The Speedmaster Broad Arrow reference 3654.20.31 features the Omega caliber 3320 with functions of hours, minutes, small seconds, date and column-wheel chronograph. The movement offers date indication and precise chronograph timing through the column-wheel system. Standard 20mm lugs for the strap.

Frequently asked questions

What is the exact lug width of the Omega Speedmaster Broad Arrow 3654.20.31?

The lug width of the Speedmaster Broad Arrow 3654.20.31 is 20mm. This measurement corresponds to the distance between the lugs of the case (measured from the inner shoulder of one lug to the other) and is the fundamental parameter for choosing a compatible strap. Always verify this measurement before ordering a replacement strap, also consulting the original Omega strap supplied with the watch.

Which strap material is recommended for this rose gold chronograph?

For the 3654.20.31, alligator (hazel brown or black), shell cordovan (for those who love leather that ages over time), and vegetable-tanned calf are ideal. Alligator creates a natural aesthetic harmony with the rose gold case, while cordovan offers superior resistance. Vegetable-tanned calf is also excellent for a patina that evolves over time, just like the metal. More casual choices include NATO fabric or technical rubber, useful for sports or travel.

How do you change the strap on the Speedmaster Broad Arrow without risking damage?

The change requires a spring bar tool (a tool with a double tip). Gently insert one tip into the slot of the spring bar, lift the strap to fully expose the bar, extract the bar from the opposite seat. The new strap is inserted by aligning its holes to the bars, then reposition the bars in the lugs. Avoid forcing to prevent damage to the case lug seat. If uncertain, contact a trusted workshop or the Casati Milano atelier for a strap change with professional consultation.

Which aftermarket straps are compatible with the 3654.20.31?

Any strap with a 20mm lug width is compatible, provided that the lug seat (the area that accommodates the strap) is constructed with proportions consistent with the model. The handcrafted straps from milanostraps.it are specifically designed for this width and customizable in leather, color, initials, and type of buckle or deployant clasp. It is important to choose quality materials (alligator, cordovan, calf) to ensure durability and aesthetics commensurate with the watch.

How long does a leather strap last on a chronograph like the Speedmaster Broad Arrow?

Longevity depends on the material, usage, and care. Quality alligator typically lasts an average of 4-6 years with moderate daily use. Shell cordovan can exceed 6-8 years thanks to its density. Well-crafted vegetable-tanned calf averages 3-5 years. Factors such as sun exposure, humidity, and perspiration accelerate wear. Handcrafted straps from Casati Milano include an 18-month warranty and can be regenerated or replaced over time, maintaining aesthetic coherence with the watch.

The next step

The right strap isn't chosen. It is built, together.

From the atelier appointment to delivery, every step is made for those who know that things done well take time. Rare leathers, one piece at a time, eighteen months of warranty.

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Casati Milano · Via XX Settembre 15, Milan · by appointment only