ICOM AD-135 14-Pin Earphone Adapter
Free
3.5 mm earphone jack adapter for use on either of the earphones SP-27, SP-29, or SP-40. ICOM AD135
This earphone jack adapter is for the ICOM Ic-sat100 Satellite radio
https://www.satmodo.com/product/icoms-ic-sat100-land-mobile-radio-lmr/