These 100 mA, 2.5 volts mini Christmas replacement bulbs are intended for incandescent string lights that require 0.25-watt lamps. It is important to double-check the wattage (or amperes) required for your light set before purchasing. The unique pinched-base shape guarantees a secure fit in most every string light (regardless of whether the pinched base is required or not). The pack includes 50 red bulbs. Please be sure to reference the tag near the male plug on your light set to confirm both the voltage and wattage for your string. Voltage, amperes, and wattage must all match the following bulb specifications: 2.5 volts, 100 mA, 0.25 watt.