Probation Period - want to add a clause of the Mandatory Probation period for six months

Hello Team, Please help me to implement the below change in a proper way, we are a small scale co. of 30 people.
We want to add a clause of the Mandatory Probation period for six months.
How to add this, I need a framed sentence which will be considered positively, legally also it is correct, as per labor law there should not be any objection from the labor point of view. Thanks in advance
Shraddha

Dear Member,
Probation Clause: " Upon joining this company, you would be placed on probation for a period of six month initially (*which is further extendable of another term of six month-optional).During probation period if your performance , conduct and discipline is found unsatisfactory, your services are liable to be terminated without notice ."
* If you may wish to give one more chance to employee than it may be added or else don't put it in condition.