ICD-10-CM > S00-T88 > T20-T25 > T23 > T23.5 > T23.50 > T23.509 T23.509 Corrosion of first degree of unspecified hand, unspecified site Non-Billable/Non-Specific Codes T23.509A..., initial encounterT23.509D..., subsequent encounterT23.509S..., sequela