Glowfly Universal Hot Surface Igniter. Glowfly has specifically been designed for service replacement jobs and brings the latest technology and OEM quality to even the oldest furnaces. The toughest technology, silicon nitride, is extremely durable, making it less prone to breakage when used in challenging installation. Optimized form factor enables quicker, easier service calls. With 6 custom designed brackets and their 7 configurations, Glowfly fits most replacement igniter applications. Match and mount simplicity: Remove the old igniter and compare it with the diagrams on the Glowfly packaging guide to determine the correct mounting bracket for the job.