There is no one-size-fits-all answer to this question, as foreign customers of Rolex watches are likely to have different preferences and styles. However, some common types of Rolex watch straps that foreign customers might prefer include:

1. Oyster bracelet: This classic bracelet is made up of three-piece links and is known for its durability and versatility. It is available in different materials, including stainless steel, yellow gold, and rose gold, and can be worn every day or for special occasions.
2. Jubilee bracelet: This bracelet was introduced in 1945 to commemorate Rolex's 40th anniversary and is characterized by its five-piece link design. It is often associated with dress watches and is available in different materials, including stainless steel, yellow gold, and Everose gold.
3. President bracelet: This bracelet is named after the US President Dwight D. Eisenhower, who was known to wear a Rolex Day-Date watch with this type of bracelet. It is characterized by its semi-circular links and is often associated with formal or high-end watches.
4. Leather strap: Some foreign customers might prefer a leather strap for their Rolex watch, as it can provide a more casual or vintage look. Leather straps are available in different colors and styles, including alligator, calf, and suede.
5. Rubber strap: A rubber strap can be a great option for customers who want a more sporty or waterproof watch. Rolex offers a few rubber strap options, including the Oysterflex bracelet, which is made of a flexible metal blade covered in high-performance elastomer.
Ultimately, the type of Rolex watch strap that a foreign customer chooses will depend on their personal style, intended use, and budget. Rolex offers a variety of straps to choose from, so customers can find one that fits their needs perfectly.