Philips Norelco shavers are generally designed for dry shaving, which means they work best without the use of shaving cream or gel. However, some users find that applying a small amount of moisturizing cream or gel can enhance the shaving experience, particularly with certain models that are specifically designed for wet/dry use. If your shaver has a wet/dry feature, it is suitable for use with shaving cream or gel, and you can safely shave under running water. For those models not designed for wet shaving, it is advisable to keep it dry for optimal performance and to avoid any potential damage. To confirm the best practices for your specific model, it is a good idea to refer to the user manual or check the product page on the Philips Norelco website, as they provide detailed information tailored to each product.