SPF stands for sun protection factor, and the number mainly describes protection against UVB rays—the part of sunlight most linked with sunburn. An SPF 60 product filters a high percentage of UVB when applied correctly; the difference between SPF 30, 50 and 60 is smaller than many people expect, but SPF 60 is nevertheless a high-protection choice for intense sun or fair skin. The Biosun spray is described as a broad-spectrum sunscreen, which means the filter system is intended to cover UVA as well as UVB. UVA rays penetrate deeper into the skin and are associated with photoaging, such as loss of elasticity and earlier visible fine lines, so broad-spectrum protection matters even on days when you do not burn.
Keep in mind that no SPF number means you can stay in the sun indefinitely. The protection achieved in real life is lower than the label number if you apply too little, miss areas, or wait too long to reapply. The source information for this product also advises avoiding deliberate prolonged sun exposure even when using high SPF, and taking extra caution with children and intense midday sun.
So this product is suitable as a step before going outside in summer, especially if your main goal is high-level broad-spectrum cover in a quick spray format.