66784 Stud Mount Valve Spring Compressor: Fit for all 3/8" & 7/16" Rocker Studs. Specially designed for compressing valve springs with the cylinder head on block. Easily and quickly remove valve spring from an assembled engine for checking or replacing. HW0107 Valve Stem Seal Pliers: Fit for most cars in the market, works with OEM and aftermarket seals regardless of their configuration. Specially designed for removes valve stem seals on overhead camshaft engines without damaging the seal. Also can be used to remove springy hose clamps. 19700 Valve Holder Hose: Commonly used when valve springs or valve stem seals are replaced. Comes with two-step fitting for both 14 mm and 18 mm threads. Heavy duty 12" flexible hose allows easy access to spark plug hole and air supply. Thread fitting to spark plug hole and other end to air supply. Air pressure helps prevent the valve from falling into the combustion chamber. SATISFACTION GUARANTEE: If you're not 100% satisfied with our item, simply return it for a full refund in 30 days. We support 12 months’ Warranty.