Kubota tractor or engine owners, having cold start issues? These XYZIL glow plugs might be just what you need to get your diesel engine firing up smoothly, especially in chilly weather. This is a set of FOUR glow plugs, which is often what you need for a 4-cylinder engine. The main part number is 15221-65510 (also cross-references to 15401-65510, 15521-65510, and others). They're 10.5V, with an overall length of 74mm and a heater tube length of 16mm. Compatibility is key here – they fit a whole range of Kubota engines including the DH1101, D1100/D1102 series, D1301/D1302, and the V1402, V1702, and V1902 engines. That means they work in a ton of Kubota tractors like the L175 through L355SS models, the M4050, M4500, and M4950 series (including the DT models and old types), plus some wheel loaders (R400, R410) and excavators (KH-28L, KH-60). It's a very long list, so PLEASE double-check your specific engine or tractor model against the detailed list in the description before ordering to make absolutely sure. Replacing worn-out glow plugs can make a world of difference in starting performance and reduce white smoke on startup. If your Kubota is getting harder to start when it's cold, this 4-pack is an affordable place to start troubleshooting. Just remember, proper diagnosis is always best – make sure the problem is actually the glow plugs and not something else in the starting system.