I bought this after watching a youtube video with tests of 5 or 6 different brands. Included how goo they sealed etc and if gunk(slime in this case) could be washed out of tyre so that it could be repaired.
Slime CRK0305-IN Flat Tyre Puncture Repair, Smart Repair, Emergency Kit for Car Tyres, Includes Sealant and Tyre Inflator Pump, Suitable for Cars and Other Highway Vehicles, 15 Min Fix Less than £25 for prime members
https://www.amazon.co.uk/gp/product/B003QHY000/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1