... damage in transportation.4) Top quality 3528/5050 SMD with big area for heat dissipation in the back is better ... in heat dissipation.5) Use an improved circuit board with reducing the total harmonic distortion (THD), to less than 20 ... .6) Discount are offered bases on order quantities. Application:Residential Lighting , office ,factory ,supermarket, hotel ,exhibition hall, parking lot, shuttle , ...