(1) direct sales. This is the shortest and most direct channel. Manufacturers directly control the marketing of products and can quickly get customer feedback. Such as trade fairs, telephone sales, vending machines, door-to-door delivery, mail order, self-operated shops by operators, online marketing, etc. All belong to this form.

(2) Single-link direct selling. Manufacturers directly wholesale their products to retailers, and then retailers sell them to users. Namely: producer-retailer-consumer.

(3) Multi-link sales type. The products produced by manufacturers are sold to users through multi-level and multi-link, generally in several forms: producer-wholesaler-retailer-consumer; Producer-agent-retailer-consumer; Manufacturer-agent-wholesaler-retailer-consumer.