The difference between the replacement gear and sprocket kits is the drive type on the opener unit. You have chain, belt and screw drive. The screw drive uses a totally different type of gear system. The chain and belt drive gear kits are almost identical. If your unit has a DC motor than the motor and gear system is all contained together in one part. As far as brands that use the same gear kits some opener manufactures make several different brands.

Chamberlain, Liftmaster and Craftsman

For example Chamberlain, Liftmaster and Craftsman come from the same factory. Genie and Overhead Door brand are made in the same factory. All these brands will use the same exact parts on each brand name opener. Also these manufacturers will put a local door companies name and logo on their openers. Any Garage door tech should recognize any brand of opener just by looking at it. If not than he hasn’t been in the industry that long. Also these manufacturers make different models and HP. and parts can be slightly different from model to model.