Strap for Elegant Collection Automatic 9 Stainless Steel / Red Gold / White

The lug width is 20mm. This measurement represents the distance between the two contact points of the case lugs and determines which straps are compatible with your watch. The 20mm dimension is proportionate to the 39mm case diameter and ensures perfect aesthetic balance between lug and strap.

For its bi-metallic elegance, we recommend natural alligator in cognac tones or vegetable-tanned calf leather in medium brown with developed patina. Both materials respect the understated character of the piece without competing visually with the rose gold and stainless steel case. Black works well for formal occasions, especially with a rose gold deployante clasp.

Use a digital calliper or millimetre ruler and measure the distance between the inner edges of the two lugs at the point where the strap makes contact. For the L4.910.5.11.7, the result will be 20mm. Alternatively, consult the official Longines documentation or your authorised retailer.

Yes, provided the lug width is exactly 20mm. Quality artisanal straps are compatible with this reference. We recommend always verifying measurements with the manufacturer and choosing leather and finishes that dialogue with the bi-metallic character of your watch.

A high-quality alligator or calf strap lasts an average of 3–5 years with regular use, provided minimal maintenance: periodic cleaning with a damp cloth, avoiding prolonged moisture and intense perspiration. Vegetable-tanned leathers tend to develop patina over time, increasing their appeal. Artisanal straps from Casati Milano include an 18-month warranty and can be regenerated if worn.