VOLTIZER 66538S Spark Plug Boot Kit with Copper Terminal & Insulation Sleeve, Replaces Briggs & Stratton 66538S 4124 493880 493880S, Fits Most 3.5–6.5HP Mower Engines — Open-Box, 23% Off

1. Precise Replacement for Common Models Replaces Briggs & Stratton 66538S / 4124 / 493880 / 493880S. Designed for 7mm spark plug wire systems used on many B&S vertical-shaft mower engines.

2. Wide Compatibility with Mower Engines Fits many Briggs & Stratton 3.5–6.5HP mower engines, including Sprint / Classic / Quattro / 09 Series / 10 Series / 12 Series / 19 Series small engines used on Troy-Bilt, Craftsman, Yard Machines and more.

3. Durable, Heat-Resistant Rubber Material Made from strong, heat-resistant rubber that offers a secure grip and long service life. Helps protect ignition wire ends from heat, vibration and moisture in outdoor working conditions.

4. Designed for 7mm Spark Plug Wires The standard 7mm plug-wire connection ensures stable contact between the ignition coil lead and spark plug terminal, improving starting performance and reducing misfire risk.

5. Easy, DIY-Friendly Installation Simple push-on installation with no special tools required. A practical replacement for worn, cracked or loose spark plug boots on common lawn mower engines.

This VOLTIZER spark plug boot replaces Briggs & Stratton 66538S, 4124, 493880, 493880S, offering a reliable and durable connection for 7mm spark plug wires. It fits a wide range of Briggs & Stratton 3.5–6.5HP vertical-shaft engines found on many lawn mowers, including Sprint, Classic, Quattro, and popular models used by Troy-Bilt, Craftsman, MTD and other outdoor equipment brands. The boot is made from heat-resistant rubber for improved durability, helping protect the ignition wire and ensuring consistent spark delivery. Easy to install and ideal for restoring proper ignition performance on common small engines.