These motors are called Tribrids, specifically for their ability to use both a nitrous oxide oxidizer, solid ABS grains, and now certified for the first time, liquid alcohol as fuels.
The K350TR-P is a 45% K motor, 1861 total NS, 853 NS max (at the start of the Tri-propellant mode), a 463 N average and a 3.89 second burn time. The thrust profile is a typical hybrid profile, albeit with an atypical difference in the initial rise to about 120 pounds for about .1 seconds, then a transition to the Tribrid phase (alcohol introduction) for a second rise to 175 pounds. From there it is straight line regressive to the 3 second point and 100 pounds, where it enters vapor phase, dropping to 40 pounds. It then does a typical hybrid tail-off to zero at the 4.6 second point. The motor total weight (pre-nitrous) is 5.3 pounds with 290 ml alcohol (.645 lbs.), .115 lbs ABS grain weight, and 1170 cc of nitrous oxide capacity. Post weight is 4.54 lbs.