These red buttons are IR factory mated with a red trigger as IR2115-D93. That red trigger has 4 easily visible slots in the underside.
Ingersoll Rand Button Kit for Ingersoll Rand 2115 and 2125 Series Impact Wrench
Ingersoll Rand Button kit for Ingersoll Rand 2135 Series Impact Wrench
INGERSOLL RAND 2131-K75 RED BUTTON KIT FOR IR 2131 MODELS WON'T FIT 2135 OR 2235
INGERSOLL RAND 2141 TK1+2141 A329 REV VALVE+2141 A93 TRIGGER+2141 K75 BUTTON KIT
INGERSOLL RAND 2145-K75 BUTTON KIT+2141-A329 REVERSE VALVE+2145-D93 TRIGGER
Ingersoll Rand 2141-K75 - Genuine Replacement 2 Red Button Kit for 2141TiMax