Thomas Major Service Kit. Kit includes Major service kit containing C85497-P ring service kit, C85512-P valve assembly service kit, C91363-P .74" stroke piston and rod assembly. Kit is compatible with standard Thomas model TA-7102. Two kits are required per unit (This item currently has a tariff surcharge which will be added to your order as a separate line item. Tariff surcharges are subject to change.)