This is a GOTOH tremolo unit. I am selling this because I replaced the tremolo unit on a guitar I built and no longer need it. The box in the image says NS510... but the contents are a 10.8mm pitch steel block type, so please be aware of this. I only replaced the unit, so the other parts (studs, tremolo arm, tremolo springs, tremolo hangers, etc.) are brand new. I believe the tremolo unit itself is also in good condition (in my opinion). *The product name was incorrect, so I have corrected it. High-quality GOTOH tremolo unit, made of metal for excellent durability. - Brand: GOTOH - Model Name: 510TS-FE1 - Type: Tremolo Unit - Included: Springs, screws, arm - Material: Metal Thank you for looking.