The yellow SD or SD+ logo means that your safety shoe has an antistatic sole.
Means that your work shoe has protection for the metatarsus of the foot.
RESISTANCE TO ELECTRIC SHOCK
Means that your safety shoe is equipped with ESR protection for 18,000 volts with a leakage current not exceeding 1mA.
CHAIN SAW GUARD
Means that your work shoe offers protection against the risks associated with the use of the chainsaw.