Saunders Firing Line Release Trainer. 

The Release Aid Checker / Conditioner / Practice Tool
Firing-Line is the ultimate tool for archers. So compact, it stows in a brief case…perfect for practicing
anywhere, anytime. With quick draw-length adjustment and 30 lb. pull its great for warming up, tuning a
release or muscles. Even better, it can overcome everyone's nemesis..target panic. Never worry about
throwing an arrow..just aim and practice the perfect release, time-after-time, after-time. With each
smooth and quiet shot you burn-in muscle memory so when its the real thing, you burn-in the x-ring.
Firing-Line..The place to practice.