The Indian constitution is often described as a combination of federal and non-federal features. The non-federal features of the Indian constitution include:

1. All India Services:
The establishment of All India Services, such as the Indian Administrative Service (IAS) and the Indian Police Service (IPS), is a non-federal feature of the Indian constitution. These services are created and controlled by the central government and are responsible for the administration of both the central and state governments. The members of these services hold key positions in the administration and can be posted anywhere in the country. This centralized control over the bureaucracy is a departure from the federal principle of decentralization.

2. Flexibility of the Constitution:
The Indian constitution is considered flexible because it can be amended by a special majority of the parliament. Unlike a federal constitution, where the powers of the central and state governments are rigidly defined and can only be changed through a complex amendment process, the Indian constitution allows for relatively easier amendments. This flexibility enables the central government to assert its authority over the states and modify the distribution of powers between the center and the states as necessary.

3. Supremacy of the Constitution:
The Indian constitution is supreme and acts as the ultimate source of authority in the country. This means that all laws and actions of the government must conform to the provisions of the constitution. In a federal system, the states often have their own constitutions and enjoy a degree of autonomy. However, in India, the central government has the power to intervene in the affairs of the states if their actions are deemed unconstitutional. This central control over the states is a non-federal feature.

4. Bicameralism:
The Indian parliament consists of two houses - the Lok Sabha (House of the People) and the Rajya Sabha (Council of States). While the Lok Sabha represents the people of India, the Rajya Sabha represents the states and union territories. The presence of the Rajya Sabha, which gives equal representation to all states, regardless of their population, is a non-federal feature. In a federal system, the states usually have their own legislative bodies with equal representation.

In conclusion, the non-federal features of the Indian constitution include the establishment of All India Services, the flexibility of the constitution, the supremacy of the constitution, and the presence of a bicameral parliament. These features highlight the centralizing tendencies of the Indian constitution and its departure from a strict federal structure.