na-adjective, noun which may take the genitive case particle 'no'
elastic; flexible; telescoping; expandable; retractable
Describes something that can freely expand and contract, physically or metaphorically. Often used for tools, materials, or abstract systems.
このポールは伸縮自在で、持ち運びに便利だ。
This pole is telescoping, making it convenient to carry.
His schedule is flexible, so he can handle sudden changes.