Pleased to be able to offer this gear.  This is for the 12" ECK Sidegear Oscillator,  This is the large adjustable gear where the oscillator arm mounts.  This gear is the same for a ball motor or tank motor oscillator.  After some product testing, some minor adjustments may be needed depending on shaft wear on the adjoining gears.  All this is fan specific and minor, the gear itself works properly.