The used Midmark Ritter Articulating Arm Board is great for surgery. 

The articulating armboard accessory attaches to either side of the exam chair or even your surgery table and supports the patient’s arm during procedures and administering of IVs. The ball joint design permits multi-directional movement. Simply squeeze the lever, position the armboard and release the lever—no tools necessary.

The Midmark Articulating Arm board is designed for Midmark exam tables and exam chairs, however it can easily work with surgical tables in the operating room.

Specialty / Medical Practice: Surgery Center, Orthopedics, etc. 

Specifications:

• Product Usage: Accessory for procedure chair or surgery table
• Brand: Midmark Ritter
• Warranty: 90 days parts and labor
  
• Dimensions: 7" x 24" x  10"
• Days to be ready: 1-2