A suitable size for top up, if required, if multiples of 5 litres is to much for you.

EVANS WATERLESS ENGINE COOLANTS

The coolant is completely water free and therefor will not boil, will not assist corrosion and operates at much reduced pressure thus improving the longevity of hoses, the water pump, seals and other cooling system components.
Evans prep fluid is used to condition the system, its primary role is to remove water from the system, 5 litres will be enough for systems up to 8 litres capacity. This part of the process is not necessary if the engine is already dry. The system is then filled with the correct amount of Evans Classic Cool 180, which is available is multiples of 5 litres.
For reference TR's have the following capacities: -
TR2-4A approximately 8 litres
TR250, 5, 6 approximately 6.5 litres
TR7 approximately 7.6 litres
TR8 approximately 11 litres

Evans Classic Cool 180 is suitable for all classic and modern cars and motorbikes. In addition we can supply Vintage Cool 180 which is specially formulated to suit vintage cars and motorbikes as well as Power Cool 180 which is suitable for racing cars and motorbikes. Please see Information sheet IS0046 for further details and Promo sheet PS0012 below for more details.

This part is listed on the following pages of the website, where further information and background reading may be found.

Hardware, Oils and consumables » EVANS WATERLESS ENGINE COOLANT
Information Sheets » IS0046 - Evans waterless coolant
Information Sheets » PS0012 - Evans waterless coolant product sheet