The Weil McLain 97+'s come in different sizes:
70k, 110k & 155k BTU inputs
The 70k and 110k use this maintenance kit:
The 155k uses this one:
DO NOT SERVICE THE BOILER WITHOUT A WM97+ MAINTENANCE KIT AVAILABLE
The WM97+ maintenance kit includes components that may have to be replaced when accessing or disassembling parts of the boiler. Failure to replace damaged components and to use only the parts specifically intended for the boiler can result in severe personal injury, death or substantial property damage.