T5 Wedge Base Bulb, 12V 18W Low Voltage, Long Life, 1XT5-12V-18W - Walmart.com
Feit Electric 18-Watt Bright White (3000K) T5 Wedge Base Dimmable 12-Volt Landscape Garden Incandescent Light Bulb (4-Pack) BPLV518/4/HDRP - The Home Depot
Feit Electric FEIT 18W XENON WEDGE BASE 12V at Lowes.com