As a professional gardener, glyphosate is essential for killing weeds down to the roots in paving, and in areas where hand-weeding is difficult or impractical. This product is excellent in that it is concentrated, enabling the user to dilute appropriately, as different weeds need different strengths. This makes it a lot more value for money than those products which already have a built- in sprayer. Such products are over priced, you get a small amount of chemical, and you can't vary the strength. Get yourself a sprayer and use this product, and it will last 10 times longer. The back of the bottle gives you detailed recommendations on dilution ratings for various weeds, and then you can simply give them a quick spray when no rain is forecast for at least 5 hours. Within 2 weeks (although largely this depends on the species of weed) you will see signs of dying in the plants. Careful though of spray drift on breezy days.
For other pro gardeners, you can get 5 litre bottles by Bayer which works out at half the price of this bottle!