PAN requirement: failure to furnish PAN by a collectee triggers higher tax collection rates and invalidates PAN-based declarations. Section 206CC requires collectees under Chapter XVII-BB to furnish their Permanent Account Number to collectors; failure or furnishing an invalid PAN triggers tax collection at the higher prescribed rate (subject to statutory cap). Declarations under section 206C(1A) and applications for lower collection certificates under section 206C(9) are invalid without PAN. The collectee must quote PAN in all correspondence; non residents without a permanent establishment are excluded, and an inoperative PAN similarly causes higher tax collection under section 206CC.