Everything is satisfactory.

Pros: Positively holds the spark plugs so that you can easily inspect both ends just by flipping the tray. Makes it easy to quickly check all plugs for resistance with an ohm meter by setting the tray on its side. Cons: Poor fit and finish, with no markings for plug positions (cylinder #, Top/Bottom). This tray is very functional, but i expected better workmanship and attention to detail for $40. I applaud the initiative to build and market a great idea like this, but none of the edges are finished (saw marks and rough edges) and the tray was assembled with gaps and glue runs where the sides are attached. The strap is attached to the sides with a single screw through the strap (no grommet) on each end. There are no markings on the plug tray to identify cylinder number or top/bottom, so youll have to do that yourself. The plug holes are tapped to allow you to screw the plugs in securely, but they all required some cleaning to remove debris before I could use the tray. I gave 3 stars because the tray is functional and will serve my needs, but it appears to be a product from a home workshop that should be priced at about $15 at most. I wouldnt have bought this at $40 if I had been able to see it first.

The reason I thought this product was a great idea was in the event it was knocked over, the spark plugs would stay in place securely. I had just purchased this and it fell out of my car seat on to the pavement and the side broke off (tag still on the product). It was a very short fall and it shocked me that it broke. After looking at the construction of the tray sides, the plastic is notched out and it doesn’t leave much material to stand up to any substantial impact. I immediately contacted Aircraft Spruce and asked if I could try a replacement before I asked for a refund. They contacted the seller and was told that wasn’t going to be an option. The company doesn’t stand by a product that can’t take a 2 foot fall of which the selling point is the secure mounting of spark plugs. Aircraft Spruce has great customer service but this product is junk. I hardly ever write a review but if it saves someone else the frustration of spending and money on this, I figured it would be well worth my time.