Strap for GMT-Master II Stainless Steel / BLRO / Oyster

The lug width of the Rolex GMT-Master 126710BLRO-0002 is precisely 20 millimetres. This measurement is taken between the two lug ears at the point where the strap inserts into the case. Verifying this dimension before purchasing an aftermarket strap is essential, as an incorrect width compromises insertion and stability. A digital calliper permits measurement with accuracy at the midpoint of the lug.

For the GMT-Master 126710BLRO-0002, natural alligator remains the most sophisticated choice due to its rectilinear grain and the patina developing over time. Calf leather is a versatile and noble alternative. Vulcanised rubber offers practicality for casual contexts and aquatic environments. Cotton-polyester NATO ensures versatility of change. Material selection depends on primary use context: formality requires alligator or calf; dynamicity suggests rubber or NATO.

The strap is changed using a dedicated tool (spring bar tool) to remove the elastic pins (spring bars) securing the strap to the lugs. Position the flat end of the tool in the access hole of the spring bar, apply gentle pressure to compress the internal spring, and slide the pin out of the lug. Repeat for both sides. Insert the new strap by pressing the pins into the lugs until the locking click is heard. Professional horology assistance is advisable on first attempt to avoid damage to the lugs.

Any strap with a 20-millimetre lug width is compatible with the GMT-Master 126710BLRO-0002. It is essential to verify that strap thickness does not exceed 3–4 millimetres, otherwise insertion into the case lugs becomes impossible. Bespoke straps from Casati Milano are realised specifically for this dimension. Generic unverified straps are inadvisable, as they risk damaging spring bars or case lugs.

A natural leather strap of quality (alligatore, calf, shell cordovan) typically lasts between 18 and 36 months, depending upon daily wear, humidity, cutaneous perspiration, and solar exposure. Leather softens progressively and develops aesthetic patina within the first months, yet begins structural deterioration after 2–3 years of daily wear. Vulcanised rubber achieves greater durability (4–5 years). Regular maintenance with leather-specific creams extends useful life. Casati Milano offers an 18-month warranty against manufacturing defects.