Item #: KDT901. Use to apply air pressure to keep valve closed while replacing valve spring. 14mm and 18mm adapters threaded for 1/4" NPT. Remove spark plug and screw air hold into port. Fasten air hose to fitting and apply pressure. Use with 912, 915, 2078, 3087, or 3271 Valve Spring Compressors. Customers also search for: Discount Air Hold Fittling Set, Buy Air Hold Fittling Set, Wholesale Air Hold Fittling Set, 082171009013, ToolWeb, Engine Valve Tools