Can works contractor avails input input on material purchased in his name

Hi,

One of My client is doing work contract business. He is providing composite supply material & labour for his client. And he is purely outsource labour contract to another sub contractor. 

1. Is he eligible to avail input on material purchased in his name (cement purchase)?

2. The above subcontractor (labour contractor) is unregistered service provider, is Main Contractor (my Client) liable to pay rcm for availing input service from unregistered service provider?

Thanks in advance

regards

K.Senthiil Prasad