Price as reviewed:
Fenwick’s FS-1 is a versatile cleaner.
Used at full strength it’s an effective degreaser, happily shifting thick grime off chains and sprockets.
Diluted, as recommended, one part to 10 parts water, it’s not brilliant, still needing plenty of elbow grease with a stiff brush to break up road grime.
A higher concentration has the desired effect – we tried 1:5, which was much better.
You'll still be getting excellent value - only £2 per litre, it's biodegradable and smells nice too.