Strap for Formula 1 Kith 35 Stainless Steel / Beige

The lug width of the TAG Heuer Formula 1 WA121F.BA0023 is 18 millimetres. This measurement represents the space between the lugs of the case and is crucial for strap compatibility. Verifying the measurement with a calliper before purchase is essential to avoid incompatibility errors.

For the WA121F.BA0023, straps in alligator or vegetable-tanned calf leather are the most appropriate choices, in dark brown or black colourways. These materials enhance the minimalist, sporty aesthetic of the watch. Alternatively, NATO straps in ballistic nylon offer maximum versatility for daily and sports use. For aquatic use, vulcanised rubber is the optimal solution.

To change the strap, you will need a dedicated lug removal tool or a small hammer and chisel. Position the watch on a protective surface, locate the spring bars that secure the strap to the case lugs, and apply gentle lateral pressure until they release. Insert the new strap by sliding the spring bars through the lug holes until fully engaged. This operation requires millimetre precision; if in doubt, consult a specialist watchmaker.

Yes. The WA121F.BA0023 accepts third-party straps provided they are constructed with an 18-millimetre lug width. Milanostraps.it offers a selection of artisanal 18mm straps in alligator, calf leather, and technical materials, all customisable. Atelier Casati Milano creates bespoke straps with personal consultation and an 18-month warranty.

A quality leather strap at 18mm, with moderate daily use, maintains structural and aesthetic integrity for 3–4 years. Longevity depends on frequency of use, sun exposure, ambient humidity, and maintenance care. Vegetable-tanned leather tends to age gracefully, developing patina; technical rubber straps have superior durability, up to 5–6 years with proper cleaning.