47681287001 is the PONC (Pneumatically Opened Normally Closed) 1/2" angle valve used on the bottom of the Ingersoll Rand Rand DA40IM-DA70IM series of modular desiccant air dryers.
47681308001 is an OEM part from Ingersoll Rand and will work with the following Ingersoll Rand air dryers:
Part #: 47685492001
Part #: 47681287001
Part #: 47681243001
Part #: 47681245001