Strap for Planetarium

The Christiaan van der Klaauw Astronomical Masterpieces CKPT7824 features a lug width of 20 millimetres. This measurement refers to the internal distance between the two spring bars (attachment pins) located on the watch case. It is essential to verify this dimension before purchasing an aftermarket strap, as straps of different widths (18 or 22 millimetres) will not fit correctly.

The best strap depends on your intended use. For formal contexts, we recommend genuine alligator in navy or cognac tones, which creates a natural aesthetic dialogue with the white gold case. Premium-quality calf leather, preferably vegetable-tanned, offers discretion and resistance to ageing. For a practical and versatile solution, FKM rubber straps provide chemical resistance and prolonged elasticity, ideal if you wear the watch in variable environments.

To change the strap on a watch with 20mm lugs, you must use a spring bar tool to gently compress the attachment pins. Position the tool beneath the pin, apply light pressure inward until sufficient clearance is created to remove the pin from its seat, then detach the worn strap. Insert the new strap by aligning the holes with the pins and release pressure to secure it. For watches of the calibre of the CKPT7824, we recommend entrusting this operation to a professional to avoid damage to the case or pins.

Yes, numerous aftermarket straps compatible with a 20-millimetre lug width exist. However, construction quality varies significantly between manufacturers. For a watch of this manufacturing calibre, we recommend straps in genuine alligator or premium-quality calf leather, produced by artisans specialising in horology leather. Avoid low-quality synthetic or eco-leather straps, which do not respect the aesthetic architecture of the model.

The lifespan of a leather strap depends on material quality, frequency of use, and environmental conditions. Premium-quality alligator or calf leather, vegetable-tanned, can last 5–8 years of moderate daily use before requiring replacement. Frequent exposure to salt perspiration, extreme heat, or prolonged humidity accelerates wear. A non-aged leather strap will have a shorter lifespan. FKM rubber straps offer greater longevity (8–10 years) due to their intrinsic chemical resistance.