Tds on job work

Dear Sir, We are a munufacturing industries in which we make Job work to our Delhi Vendor, His Bill Stracture as follow:- Total Value Rs. 100000.00 Less:- Job Work charges Rs. 20000.00 Net Value for Material Rs. 80000.00 CST 2% on 80000.00, Rs, 1600.00, Then total bill value is Rs. G Total Rs. 100000.00 CST Rs. 1600.00 Total Amt .Rs. 101600.00, Hence plz suggest me that on which amt we will charge TDS ?.