I think it has been used very little. Contents: ・2 types of replacement keycaps (with markings / without markings): 4 pieces ・Keycap puller ・Instruction manual (replacement procedure, key layout chart) ・This is a color keycap set compatible with the HHKB Professional series. ※ Can be used with the following HHKB Professional series: HHKB Professional HHKB Professional 2 HHKB Professional JP HHKB Professional 2 Type-S HHKB Professional JP Type-S HHKB Professional BT HHKB Professional HYBRID Type-S HHKB Professional HYBRID HHKB Professional Classic Type-S HHKB Professional Classic Cannot be used with the HHKB Lite2 series or HHKB Studio series. ・Please use it to replace the ESC (green) key and Control (blue-gray) key keycaps.