1043
Metallic cellular solids are a class of materials known for their high specific mechanical properties , being desirable in applications where a combination of high strength or stiffness and low density are important .
 Metallic, materials, mechanical properties, strength, stiffness, density
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: manufacturing standard, machanical property, manufacturing process, material, engineering feature, process parameter, machine or equipment, application, process characterization, enabling technology, biomedical, concept or principle 
Text: {0} 
Answer:
 Metallic, materials, mechanical properties, strength, stiffness, density