there is a huge conglomerate that owns most of these tool mfg. as such since they have been involved quality has slipped substantially. so a partial list :makita, roybi dewalt,milwaukee, lots more i can't remember. repair parts and service are falling behind or simply do not exist. customer service has gotten pretty poor. I have a gas powered roybi multi head trimmer unit been waiting on a part for 6 months. (course ryobi like makita has gone all electric and are basically ignoring any gas items at this point).