A weigh sling is fish-care equipment first and weighing equipment second.
It needs to support the carp properly without damaging fins or allowing the fish to slide around dangerously.
Good carp slings should have:
Soft fish-friendly material.
Strong handles.
Good drainage.
Reliable zips.
Secure retaining points if designed for short-term retention.
And enough room for the size of carp present in your water.
Floating retention slings are particularly popular because the same product can be used for weighing and briefly holding a fish safely in the margin while you organise photographs.
But retention should always be kept to the minimum necessary and follow fishery rules.
Brands including Trakker, Fox, Nash, Korda, Aqua and Solar all produce dedicated carp slings.
I’d also check the wet weight of your sling before fishing.
Nothing ruins an accurate fish weight like guessing how much a soaking wet sling weighs.
Which carp sling do you trust with your biggest fish?