This week, Roborock announced that its highly anticipated Saros Z70 is now available for pre-order. The Z70 features a robotic arm and is one of the most expensive robot vacuums in the world, at $1,899. For the launch, Roborock is sweetening the pot by bundling the new bot with the choice of a free second vacuum cleaner.

The Saros Z70 was announced at CES this year and is the first mass-produced robot vacuum with a robotic arm. The OmniGrip arm extends from the robot to pick up small items, including socks, tissues, and sandals, to help it clean your home more effectively. The Z70 also boasts 22,000Pa suction power and Roborock’s new StarSight navigation system that combines 3D sensors, cameras, and machine learning to navigate as well as identify and avoid obstacles.

The new robot vacuum features an “AdaptiLift Chassis,” which Roborock introduced on the Qrevo Curv and allows the robot to get up and over high transitions between rooms. There’s also two-in-one mopping and vacuuming capabilities and a multifunction dock that cleans the robot’s dual-spinning mop pads and fills its water tank, as well as emptying its dustbin.

Roborock is offering those who pre-order the Saros Z70 the choice of a free vacuum, with the option of one of eight of its other models. On offer are several upright wet/dry vacs, plus two brand new robot vacuum models. The Qrevo S5V is a lower-priced version of the Qrevo Curv but without AdaptiLift Chassis, according to Roborock spokesperson Ruben Rodriguez, and the Q10 S5 Plus is a less feature-rich version of the Qrevo Edge.

Roborock hasn’t announced pricing for these new Q models, so it’s not clear how good a deal this is, but the Qrevo Curv retails for $1,599.99. Among the other vacuums it’s bundling is the Dyad Pro Combo, which retails for $659.99.

The buy one get one free offer helps somewhat with the sticker shock of the Z70, and until robots can climb stairs (which doesn’t feel that far away), it can be convenient to have a second robot vac.