the following are the list of top video intercom system manufacturers :

1. hangzhou hikvision digital technology co. ltd in China
2. Videx Electronics SPA
3. Infiniteplay Srl
4. hangzhou hikvision digital technology co. ltd
5. fermax electronica sa in Spain
6. Guangzhou Video-Tech Electronics Co. Ltd in China
7. vandsec electronics limited in China
8. Textel Technologies Pvt. Ltd in India