This is the Orion Delta heated build plate (bed) that's used on our machines.  Smooth Black finish, centered thermistor hole for included 100K NTC thermistor, LED indicator for power on, and features all the electrical connections on the bottom side for a clean top surface for attaching a build plate to, such as our 220mm boroscillicate glass build plates.  It comes with a lasercut insulator to mount underneath the bed to help with heating times as well as retain heat, 6 4-40x3/4" mounting screws, 6 blind nuts for attaching to your printer, and the LED/Resistor for indicating the power status.

This heated bed is also a great size for DIY builds as well as an upgrade for similar sized machines such as deltaprintr.

Specifications:

• Overall Diameter: 220mm
• Mounting hole spacing: 6 equally spaced holes 210mm diameter
• Resistance: Appx. 1.2 Ohms @ Room temperature
• Thickness: 3mm PCB material