Cooling shots let you convert any longfill into an iced version on demand.

A cooling shot is a small 10ml bottle of concentrated cooling agent that you add drop-by-drop to a finished e-liquid. Two different products dominate the UK market. Koolada (trade name for the compound WS-23) is a flavourless cooling agent that produces a chill sensation on the throat without adding any mint or menthol taste. Menthol concentrate adds both cooling plus a recognisable mint flavour. Both are commercially available from UK vape suppliers plus both comply with the Tobacco and Related Products Regulations.

Cooling shots solve a specific problem. Most longfill ranges are split into non-ice plus ice variants. If you like the strawberry flavour in the non-ice version but wish it had a cooling kick, you would normally have to buy the separate strawberry ice bottle. With cooling shots you can turn any non-ice flavour into an ice version by adding drops at the moment of mixing. Better still, you control the intensity. Ice versions from manufacturers typically land at a fixed level of cooling. DIY cooling lets you dial it in.

The process is simple. Mix your longfill with its Mixer Kit as normal. Once the 60ml bottle is full, add cooling drops using the dropper built into the shot bottle. 15-20 drops gives mild cooling. 30-35 drops gives medium ice. 40-50 drops gives strong ice. Shake well. Test with a few puffs. Add more in 5-drop increments if you want stronger cooling. It is easy to add more but impossible to remove so always start at the low end of the range.

Which cooling agent should you pick?

For fruit flavours either works well. For dessert or tobacco flavours koolada is usually the safer pick because the flavourless cooling does not clash with vanilla, caramel or tobacco notes. Menthol concentrate adds mint which can be jarring in a custard or pipe tobacco profile. For pure menthol lovers who want more cooling in an already mint-leaning flavour, menthol concentrate is the obvious choice since it reinforces the mint character.

One practical note. A cooling shot uses up a little of the bottle volume so if you are precise about your final strength, the added drops marginally dilute the nicotine. Adding 40 drops (roughly 1.5ml) to a 60ml bottle represents about 2.5 percent dilution, which is usually negligible for most vapers but worth knowing if you are fine-tuning a specific strength target.

• Koolada. Flavourless cooling. Works with every flavour profile. Pure WS-23 compound.
• Menthol concentrate. Cooling plus mint flavour. Best paired with fruits or menthol-compatible profiles.
• Dosage rule. Start with 15 drops per 60ml then build up by 5-drop increments.
• Safe limit. Stay under 5 percent of total bottle volume which is roughly 60 drops.

For more context on longfills including mixing walkthroughs, strength selection plus flavour steering, head to our complete Nixer vape review hub where every practical UK longfill question has its own article.