Adjustable Grill Heat Plate, Porcelain Steel Grill Burner Cover, 5 Pack

In original packaging item, may require some assembly. See link for more details:

Size: Extends from 11.75" up to 21" Length, 3.75" Width

Replacement Parts for Gas BBQ

https://www.amazon.com/Unicook-Adjustable-Replacement-Porcelain-Extends/dp/B0CSYL4LHP/ref=sr_1_2