i accidentally ordered an stp harness for my medium packy. it doesnt really fit through the hole but i spent $22 on the harness. could i just cut the hole with scissors to make it bigger and wear it with my packer or is there another way to keep my packer in place? i also think i got it too small but idk how harnesses are supposed to fit. it feels kind of like it could slide off and it doesnt cover the genital area well. idk if thats how its supposed to be or if i got it too small

The harness should be tight. Mine doesn't cover the genital area, but sits the packer in line with the clitoris like it should be situated. I usually open the hole the packer goes through with my fingers, pull the packer through, and then put it on and get situated.

If it feels like it's going to fall off, it's probably not the right size, but unless they're the same cut as underwear, they do feel a little odd the first few times you wear it.