This refers to a Tandem dual-chamber cannabis disposable vape, which combines Lemon Tart (a Sativa for energy/daytime) and Kosher Kush (an Indica for relaxation) in a single 2-gram device. 
 
Tandem Device Features
Dual-Chamber Hardware: The all-in-one disposable allows you to switch between the two different strain profiles using a built-in switch.
Strain Profile (Lemon Tart): A citrusy Sativa known for uplifting and cerebral effects.
Strain Profile (Kosher Kush): A celebrated, rabbi-blessed Indica with heavy, calming body effects.
Oil Type: Typically contains high-terpene live resin.