7249
These unique features enable a rapid prototyping of millimeter to centimeter-sized objects involving 3D architectures with true freestanding subunits and micrometric feature reproducibility .
 rapid prototyping, 3D, feature
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:
 rapid prototyping, 3D, feature