Product description: 1) Only uses a AA battery to charge a cellular phone 2) Provided mostly cellular phones Product specifications: 1) Output voltage: 6V, charge mostly cellular phones and MP3 / MP4 2) Charge time: up to only 2 hours of charge time 3) Safe protection: overflow current and short circuit protection Product features (ET501A - common type): 1) Using a 1.5V AA battery 2) Charge current: 250mA, up to 450mA (varies with usage conditions) 3) Inner circuit can be seen due to cap consisted of transparent PC material 4) Sleeve color: red, blue, black and silvery 5) Red LED indicates the charge course 6) Provided with 12 phone-specific connector plugs 7) Sleeve dimension: φ21 x 72mm Product features (ET501B - gift type): 1) Using a AA battery 2) Charge current: 250mA, up to 450mA (varies with usage conditions) 3) Cap is consisted of metal and ground-in glass 4) Conveniently customize your logo (laser, oxidation or silk-screen workmanship) 5) Blue LED indicates charge course 6) Provided with 12 phone-specific connector plugs 7)Sleeve color: red, blue, black, silver and iron-gray 8)Sleeve dimension: φ21 x 72mm Product features (ET501C- extend type): 1) Quickly charge cellular phone battery with two AA batteries through extended sleeve 2) Charge current: 400mA, up to 600mA (varies with usage conditions) 3) Cap be consisted of metal and ground-in glass 4) Conveniently customize your logo (laser or oxidation silk-screen workmanship) 5) Blue LED indicates charge course 6) Sleeve color: red, blue, black, silver and iron-gray 7) Sleeve dimension: φ21 x 118mm Order guide: 1) Product type: common / gift / extend 2) Product colors: red / blue / black / silver / gray 3) Approval: CE / FCC / RoHS 4) Packing way: small plastic bag for simple packing; mini paper-box for transport; standard paper-box; suck mould packing for market sales; round tin-box for gift 5) Enquiry: need to fill in standard price enquiry form for urgent charger En-Tron