The adapter clicks in directly onto the chassis of the stroller and most infant car seats can be strapped on the adapternUniversal Adapter High is recommended when using in combination with one seat; One High and one Low adapter is necessary for twinsnAccepts most infant car seats on the market; Please view manufactureru0026#39;s website for current listnThe adapter clicks in directly onto the chassis of the My Duo stroller and most infant car seats can be strapped on the adaptor. Universal Adaptor High is recommended when using in combination with one seat. One High and one Low adaptor is necessary for twins.