The Feinwerkbau 601 is a .177 calibre, single-stroke pneumatic target air rifle known for its precision and adjustable features, particularly in the realm of target shooting. It was a modified version of the FWB 600, distinguished by the addition of a cocking lever safety device. 
Here's a more detailed breakdown of the Feinwerkbau 601 specifications:
General:
Manufacturer: Feinwerkbau (FWB)
Model: 601
Type: Single-stroke pneumatic target rifle
Caliber: .177 (4.5 mm)
Production Years: 1987 - 1995 
Physical Characteristics:
Weight: 9.9 lbs (approximate)
Length: 51.2 inches (approximate)
Barrel: 25-inch round barrel
Stock: Laminated wood
Finish: Typically blue 
 
Performance:
Velocity: 585 fps (approximate)
Muzzle Energy: 5.0 FP (approximate)
Accuracy: Excellent, often cited for its precision in target shooting
Cocking Method: Sidelever
Cocking Effort: 19 lbs (approximate)
Trigger: Match-adjustable
Safety: The 601 features a cocking lever safety that prevents the lever from springing back during cocking, according to the Feinwerkbau website.
Rifling: 12 grooves 
 
This Rifle is in Excellent Condition for its age. The rifle has been Fully Checked and Tested with valve and Piston seals replaced and a full internal clean.