Tax collection at source: higher TCS rate applies where buyer is an income-tax non-filer under applicable law. Tax collection at source must be effected at the higher of two alternatives where the buyer has not filed an income-tax return by the due date: twice the rate otherwise prescribed for the transaction or a fixed percentage floor. This rule applies on account of the buyer's non-filer status and increases the seller's obligation to collect tax on receipt for sale of goods.