Garden hoses are commonly green and often black, but can also be found in a variety of other colors. Garden hoses are typically made of synthetic rubber or soft plastic, reinforced with an internal web of fibers. As a result of these materials, garden hoses are flexible and their smooth exterior facilitates pulling them past trees, posts and other obstacles. Garden hoses are also generally tough enough to survive scraping on rocks and being stepped on without damage or leaking. Most garden hoses are not rated for use with hot water, and their packaging will generally specify whether or not this is the case.