Is the PLM03 compatible with other brand's accessories which I have?

PLM03 uprigtht's size is 2" * 3" and hole spacing is one inch. If your accessories are compatible with PLM03 size, then you can use your own accessories.

Recommended

How to Achieve Powerful, Defined Legs from Home with the Leg Press Hack Squat
Jhon Kenneth Delos Reyes·
How to Achieve Powerful, Defined Legs from Home with the Leg Press Hack Squat

The Ultimate Guide to Finding the Right Leg Press Hack Squat Machine for You
Jhon Kenneth Delos Reyes·
The Ultimate Guide to Finding the Right Leg Press Hack Squat Machine for You

No More Judgement Zones: Train in Confidence with a Major Fitness Home Gym
Jhon Kenneth Delos Reyes·
No More Judgement Zones: Train in Confidence with a Major Fitness Home Gym