Check the listing for details. 4 Style D Mini Bulb Flashers Christmas Tree Lights Replacement Bulbs 2.5 V 0.425. Condition: New. Listed at 12.79 USD. Attention: Make sure your light string uses 2.5 volt 0.425 watt incandescent bulbs and a style D base. These will not work with LED lights. Using these in a light string with the wrong voltage or wattage will burn out the bulb quickly, or not give it enough power to flash your lights. It can take a minute or two for these to warm up enough to make your string flash. Style D base measurements are in the pictures. 4 flashing bulbs to make your lights flash. 2.5 Volt .425 Watt 0.17 Amp replacement Mini Bulb Indoor/outdoor Christmas tree flasher lights. Commonly used on 50,100 and 150 light strands, smaller strands usually use a higher voltage bulb. You can also put these bulbs in different styles of bases to make your light strand flash as long as the voltage and wattage is the same and your string uses the standard style of mini bulbs. There are many different base styles, please look at the pictures for a base D measurement diagram. I also have other flashers listed with different wattages, voltages and base styles. Video:https://youtu.be/C_QlAzvG1nU In the above video these are the regular flashers not the slow flashers. JL Missouri Parts has been selling on Ebay for well over a decade. We are constantly expanding the line of parts we offer. We are a small family run business. NOTICE: We ship every weekday, expect a business day before your item is shipped. Everything is shipped with Tracking. If you have a problem with your purchase please contact us and we will do our best to resolve it. I use calculated shipping, so if you are interested in multiple items I am selling add them to your cart and the shipping will be combined by Ebay’s system. International Buyers: Do to the high cost of shipping, I cannot accept returns. Please be sure you know what you are buying. Understand that I cannot control shipping after it leaves my possession, and it can take months to get to you. 11-18 300/ R8-21 1000