The Delhi Metro Rail Corporation today(18 July, 2007) announced that its smart cards can now be purchased for a minimum value of Rs 50 only against the earlier minimum of Rs 100. (プリペイドのカードは50ルピーから買えるようです。)The value of the card can be increased in multiples of Rs 50 upto a maximum of Rs 800. (チャージは50の倍数ででき、上限は800ルピーのようです。)The security deposit of Rs 50 which is refundable will continue to be charged, a DMRC spokesman said today. (デポジットで50ルピーが必要ですが、カードの返却で戻されます。)The card works as a prepaid device which will allow commuters to travel specified routes via rail without worrying about cash. (小銭の心配をしなくてもいいのがプリペイド・カードの一つの利点ですね。)