Review on Iverntech 400Mm MGN12 Linear Rail Guide With 2 Black Stainless Steel MGN12H Carriage Blocks For CNC Parts And 3D Printer Upgrades by Christopher Morgan

While the rails did ride smoothly, I had to remove the block, for hole alignment under my print bed support. Much to my dismay, I saw that both sides contained gaps with missing ball bearings. This led to having more fall out, when I tried to replace the block on the guide rail. I had to spend a great deal of time on Pyle carpet, fishing out tiny bearings with a neodymium magnet. This is frustrating, to say the least. There were far too many missing, to begin, and now the rail is noticeably less smooth. The entire purpose for purchasing this type of rail is to insure the smooth ride of a print bed. Iverntech MGN12 300mm Linear Rail Guide with MGN12H Carriage Block for 3D Printer and CNC Machine If you're looking for a QUALITY product, It's not always a good idea to look for the lowest price. I took a chance, and it backfired.Update: 2018/06/25As is always the case, great customer service goes a long way in improving a customer's experience with either a product or service. Though my initial experience was one of disappointment, I also understand that manufacturing defects will occur, as we live in an imperfect world. When a company places importance on customer satisfaction, it shows. This is the case with Iverntech, as their immediate response to my review was to correct the issue. They have provided me with a replacement means for a brand new block, and did so without hesitation or objection. This level of immediate response is becoming increasingly rare, and merits recognition. I have increased the rating from 2 to 4 stars. I can't give a 5-star review, as having to make a correction to a high-precision part is decidedly inconvenient. Four is the best that I can do but, if there was a way to rate their service apart from their product, Iverntech would DEFINITELY receive a five-star rating. I must recant my initial comment regarding price/quality. Kudos, Iverntech.