Back in the day when climbers were tying in around their waist and climbing in hobnail boots, their only protection was looping the rope around horns or chockstones wedged in cracks. This gave a British climber the idea of filling his pocket with rocks and pebbles to jam in cracks with webbing around, thus passive pro was born.
Thankfully, things have evolved somewhat since then with Wild Country’s beautifully made and color coded “Rocks”. They come in sizes from 1 to 14 giving protection from 0.2” through to 2”. That whole range of sizes will weigh in at approximately the weight of 4 cams, giving 15 placement options instead of 4. Rocks are the foundation of most climbing racks, especially at places like Lumpy Ridge. These Rocks taper in lots of directions giving the option of placing in flares and conventional placements. I have always been a big fan of Rocks and it is not just my British roots. Having taken a 20 foot whip onto them, I have a lot of faith in their holding power and strength. Wild Country also makes super light Alpine Rocks with a single wire and Rockcentrics to complete their passive pro lineup.
Now that you have gone out and bought your Rocks, you need to think about how to place them safely. What does a good placement look like? Should I extend it? Can I just use Rocks in a belay? Sounds like you need a Colorado Mountain School private day or a rock climbing course like Learn to Lead Trad and have an expert tell you how to place a good Rocks!