Reinforcement bar deformed is commonly used as a reinforcing material in concrete structures, including columns, beams, slabs, and foundations and used in conjunction with reinforcement bar plain. The irregular surface provides better adhesion, preventing the steel from slipping within the concrete. 

"TS" stands for "tensile strength," which is a measure of the maximum stress that a material can withstand while being stretched or pulled before breaking

TS 280 has a tensile strength of 280 newtons/mm², which would be approximately 28.196 kg/mm² 

TS 420 has a tensile strength of 420 newtons/mm² which would be approximately 42.749 kg/mm² 

Therefore TS 280 concrete steel is generally used for building construction that does not require very high strength, such as residential homes or small commercial buildings. Meanwhile, TS 420 concrete iron is used in building construction that requires greater strength, such as bridges, high-rise buildings, or industrial construction projects.

TS 280 and TS 420, adheres to the SNI standards of steel. 

When using reinforcement bar deformed, it's crucial to follow structural engineering specifications to ensure adherence to structural requirements.

SNI 2052:2017