LayLax PROMETHEUS EG Tight Bore AEG Inner Barrel Series
Inner barrel bore width of 6.03mm with a tolerance of ±0.01mm, made of stainless steel for superior strength necessary to maintain accuracy without the need for coatings. 
The barrel is arguably the heart of any airsoft gun and determines various performance factors such as velocity (FPS), accuracy, and precision (consistency). Real steel guns have a single metal barrel while airsoft gun barrels come in two pieces, an inner and outer barrel. The outer barrel reproduces the appearance of a real steel barrel, while the inner barrel is the actual barrel which fires the BB.
Inner bore width of φ6.03mm with a ±0.01mm tolerance!
Solid BB stability and accuracy, made with enhanced stainless steel (SUS) material!
 
Details:
Length: 285mm (matched length for Tokyo Marui Next Generation CQB-R  / MC51)
Inner diameter 6.03mm
Outer diameter 8.5mm
Stainless Steel (SUS)