Three shapes of stainless steel ring holder necklaces:

1. (Shell Shape):
- **Material**: High-quality stainless steel with a smooth, polished finish for durability and shine.
- **Type**: Ring holder necklace, designed to securely hold rings during work or activities.
- **Size**: Approximately 2.5 cm in diameter with a delicate, rounded shell design.
- **Shape**: Shell-shaped, with a gentle curve that mimics the natural shape of a pearl shell.
- **Weight**: Light, around 15-20 grams, making it comfortable for everyday wear.

2. (Half Moon Shape):
- **Material**: Stainless steel with a brushed matte finish for a sleek, modern look.
- **Type**: Ring holder necklace, ideal for women who need to remove and store rings during work.
- **Size**: Roughly 2.8 cm in length, with a crescent shape that allows easy attachment of rings.
- **Shape**: Half moon, symbolizing simplicity and elegance.
- **Weight**: Lightweight, around 18 grams, providing a balanced feel.

3. Rhomboid Shape:
- **Material**: Stainless steel with a high-Polish finish for a reflective, eye-catching surface.
- **Type**: Ring holder necklace with a focus on both form and function.
- **Size**: Approximately 3 cm in height, shaped like an elongated diamond.
- **Shape**: Rhomboid, giving it a geometric, modern aesthetic.
- **Weight**: Slightly heavier, around 25 grams, for a more substantial feel while maintaining comfort.