As a hesitant buyer, I was impressed with this industrial and scientific knockout hinged and its performance .As my tests showed it was easy to install and fit perfectly. The hinged design also made it very convenient to access and adjust the wiring connections, even in tight spaces. The quality and durability of the product is undeniable and it will surely last for a long time. The only downside I can think of is its price, but the superior quality makes it worth the investment..