AT&T SynJ SB67148 Two 4 Line Deskset Cordless Phone Plus Expandable Handset Bundle Accessory Deskset for the AT&T SB67118 System. Unique Value Proposition of the SynJ Cordless Deskset Intercom feature for conversations with a cordless handset, a cordless headset or the SB67118 main telephone base. Designed for the stationary employee who would prefer a Deskset experience as opposed to a handset.