The Adams Rite EX88 and EX89 End Caps are for the EX Series Interlocking and Pullman Rim Devices. The package includes the hinge side and latching side covers, along with the mounting screws.
The Adams Rite 31-0265-01-IP is used on the current versions of their devices for Cylinder Dogging. Cylinder Dogging is when you have a Mortise Cylinder to lock the device in the unlocked positions (Dogged). Very similar to the Hex Key Dogging Assembly, but the mounting plate is longer.
The Adams Rite 31-0619 is the Circuit Board that controls the Motorized Latch Retraction on the 8000 and 3000 Series Exit Devices. It is also known as the PCBA: SE Main (Black).