All OEM Yamaha Parts. Flugelhorn YFH-8310Z(S) 2010-2022 valve tune-up kit. 3 each guides, guide washers (metal), springs, valve stem & top cap/finger button felt washers. Includes 2 valve slide Orings & 3 water key rubber corks (pads). If in doubt, email me with your model. Please note Yamaha YFH-631, item # 16050 is a different kit, more common, & uses a larger spring.