Features of oligopoly market are :
(1) Few Sellers : In this market structure, a few firms dominate the market for a commodity which can impact market price of the product.
(2) Non-price competition : Under oligopolistic market there is huge interdependance between firms. As a result of which non-price competition is seen between the firms as they try to avoid price wars. Hence, price do not change frequently.
(3) Importance of selling cost : In this market their is intense competition and interdependence of firms, the firms compete each other through various sales promotion measures like discounts, advertisement, etc. Therefore, there is a great importance of selling costs and advertisement under oligopoly market structure.