Laser levels have either green or red lasers. ... Bosch GLL50-20G 50 Ft Green-Beam Self-Leveling Cross-Line Laser. $118 at Amazon. $118 at Walmart $119 at Lowe's. Pros. Bright green beam is easy ...

Laser beam helps deter Canada geese at park in Pennsylvania 01:59. A new high-tech method is keeping Canada geese away from Blawnox Community Park. Canada geese have been around western ...

Two green petawatt lasers beams collide at the focus with a third red beam to polarise the quantum vacuum. This allows a fourth blue laser beam to be generated, with a unique direction and colour ...