Camping world had a sale last fall. I'm not sure how much we paid for it, but it was like $10-15.
Its a wooden cutting board with rubber feet. The feet sit in the burner slots. A nice thing about it, it adds extra counter space, and when we travel, it prevents any rattle/noise from the burner tops.
We have had one of them for 5 years now, it is a great addition and has never come off the stove in all our travels on some very bad roads.
John & Deb
2011 F250 Lariat FX4 Crew Cab 6.2
2011 Flagstaff V-Lite 30WRLS
Days Camped 2013: 16 2014: 5 2015: 3