Tds under section 194c

Dear Sir/Ma'am,

Please suggest how to deduct TDS under section 194C:

1. Contract with vendor/ party is for fixed rate to repair a jig (say Rs. 300 for repair a jig).

2. Vendor/ party bifurcate material and labour charges in their invoice for payment of vat on material used during repair (simply 80% of total contracted price).

now the issue arise is how to deduct TDS

1. whether on contracted price (i.e Rs. 300)

2. whether on labour charges only, mentioned in invoice.

Please suggest...