The glow plug is a crucial part of your RC nitro engine. Without it, you'd be going nowhere fast! Glow plugs are available in different heat ratings for different conditions, but as with nitro fuel, we reccomend sticking to a good quality brand such as HPI or OS glow plugs for good performance. Unfortunately, there's no gauranteed lifespan on a nitro engine glow plug, however a well tuned engine should last several months on a plug. If you are frequently blowing glow plugs, it could be a sign your engine simply needs tuning - although it could also be a sign of wear. One thing is for sure - always make sure you have at least one a couple of spare glowplugs in your nitro toolbox as it's the one tiny thing that will stop your fun dead in it's tracks!