This is the coolant level probe / sender that sits in the expansion tank. Rolls Royce Silver Spirit (chassis 31001-59368), Silver Spur (chassis 31002-66587), Silver Dawn (1995-1998, all chassis),...

This is the expansion bottle, also know as the heater tank. From VIN 20001 onwards  1987-1998 Silver Spirit, Silver Spur, Mulsanne, Turbo R 

This is the cap for the expansion bottle JNV121407. 1987 From VIN 20001 onward