405-G-2 glass lens  is perfect for High power Blue laser DIYers ,short focus distance 4mm ,less dissipation, enhance the aperture optical power 

High quality glass optical lens and with coating 

 

 

Lens Material:High quality coating glass,applied for all blue and violet laser products 

Lens holder size: M9*0.5,Length :9mm

Lens size:6.33mm diamater

 Light transmittance:>98%

lens focal length: 4.02mm

 Back focal length: 4.8mm

Distance to LD : 2.357mm