Battery operated light up Beer GlassAutomatic Water ActivatedSize: 500mlMade from durable acrylic our great led glasses will bring a touch of sparkle and entertainment to any party, birthday, wedding or function. Simple to use, just add liquid and they will turn on.With their great water activated sensor light, when liquid is added they will turn on and flash until dried. Reusable they can be used again and again and they come with replaceable button batteriesOnce they start flashing they will provide a great night light and alternate colour providing a disco light effect. Ideal as hot tub accessories, sit back and enjoy the bright night light as you soakAn excellent addition to any party, being both practical and funWith a volume of upto 500ml they are a great tumbler glass which are ideal as beer, cocktails or as gin accessories and gifts for people. They will be well received by anyone and make them smile To clean - you do this by hand washing them DO NOT submerge in water