Surety bond liability continues for dealer tax defaults; surety may end obligation only after notice and remains liable for prior defaults. A Central surety bond whereby a dealer and a surety are jointly and severally bound to indemnify the Government for the dealer's Central Sales Tax liabilities, losses, costs and expenses arising from defaults. The Commissioner's written demand as prescribed triggers payment. The bond imposes continuing liability on the dealer and surety, surviving death, dissolution, insolvency or winding up, and the Government's forbearance or extensions concerning the dealer do not release the surety. The surety may terminate only after twelve months' written notice, and stamp duty is borne by the Government.