Why Our Bath Range is SLS and Parabens free ?

Because SLS (sodium lauryl sulphate) is a detergent commonly used in cosmetic products and in cleaning products as degreaser. SLS may irritate your skin, causing inflammation (dermatitis). This can produce symptoms such as dryness, coarseness and redness of your skin.
Parabens are preservatives used in many products as fungicidal and antibacterial agents. Parabens are  becoming controversial due to its presumably toxicity.