Open one microdart square for one closed bump, and leave the rest sealed. A crushed cone, or a square you peeled an hour early, goes in the bin.
Hydrocolloid is the cheap round disc, roughly 15–40p. Use it when a spot is open, weeping, or already a whitehead. It collects fluid on the surface. A microdart is a small square of dissolving cones for a closed early bump, typically £0.60–£2.50 or more each. Check the shop. If the spot is deep, painful, cystic, or it keeps coming back, see a GP. A patch is not a cure. If you are still choosing a format, start with hydrocolloid vs microdart.
Check the spot before you open the pack
Look at the bump before you tear a sachet.
A whitehead, broken skin, or any fluid means a hydrocolloid disc. Those steps are in the overnight hydrocolloid guide. A cone on that spot spends the dear patch on the wrong job.
A microdart square is for a bump that is still closed. There is no white head, and nothing is leaking. If a cheap disc stayed clear after a proper night, there was often little fluid on the surface. That morning is the unchanged-bump guide. Leave the bump alone. A pick opens it, and a cone was the wrong next step.
Revolution Super Dart is a pack of 9. Take one square. An under-eye oval is a different box. See the dissolving patch guide.
Open one square and close the rest
Open only the sachet or the tray unit you are about to wear.
If several squares share a tray, lift one and put the film or the lid back at once. Leave the others on their backing, inside the packet. A pot or a makeup bag collects fluff and cream, and a loose square bends easily.
A square off its backing has one wear left. Peel it when the bump is clean, dry, and in front of you. The press-on order is in the microdart apply guide.
Peel the backing without crushing the cones
Hold the square by the edge, or by the tab if the pack has one. Peel the backing off slowly.
Keep your fingers off the cone side. The tiny cones are the part you paid for. A pinch flattens them, and a flat grid will not sit the way the fresh square did in the tray.
If the square folds, the cones crush, or the sticky side grabs itself, bin it. A patch that has already touched skin is finished too. It is single use. Do not put it back in the sachet or onto a second bump.
Revolution Super Dart puts the cones on a small hydrocolloid dome. Skin Choice Classic Darts are a plain square. Peel both with the same care. A weeping whitehead still wants the cheap round disc.
Keep the spare patches sealed
Spare squares belong in the packet they came in, closed, on a dry shelf or in a drawer at ordinary room temperature.
Shut the foil. If the pack is a tray, press the film back down. A tray left open beside the bath lets the next square get wet, dusty, or bent. Keep the packet away from open cream, serum, and SPF. A smear on the glue is a common reason the first night lifts.
Leave each cone sealed until the bump is there. A cone flattened under a bottle is already spent. The travel packing guide is the same rule in a washbag.
Read any storage line on the carton and follow it. If the carton prints none, a cool dry cupboard is the ordinary place. Let a cold pack warm to room temperature before you peel, so the film does not tear.
A box on a sunny windowsill, a radiator, or a car dashboard can go soft. Squares then stick to the film or to each other. Move the pack into the cupboard. Open the sachet once the bathroom has stopped steaming, with dry hands.
Read what is printed on the box
Turn the carton over when it arrives, or when you pick it up in a shop. Look for a printed date, a lot code, or a batch number. Some packs show a month and a year. Some show a short code. You can photograph a code. Those letters do not become a packing month at the kitchen table.
If a date is printed and that date has passed, stop. Use the seller’s returns route and leave the sachets sealed. The old-stock guide covers the seller and the carton on Amazon UK. This page is the packet already in the house.
Look before you peel the backing. A split pouch, a crushed corner, or cones that are already flat are a reason to pause. Photograph the square and the mark on the box if you write to the seller.
A clear square in the morning is a weak sign that storage went wrong. Check that the cones sat on the bump, and that you left it on for the night. A microdart square does not go white the way a hydrocolloid disc can. That colour is the white-centre guide.
Where to buy in the UK
Revolution Super Dart (Amazon UK) is cones on a hydrocolloid dome, often listed around £5.51–£9 for 9 patches. Skin Choice Classic Darts are the plainer square, often listed around £10.99, and Holland & Barrett stocks that range. Check the price on the day. Microdart patches here are typically £0.60–£2.50 or more each.
Shops where you can hold the carton first are on where to buy microdart patches. For an open or weeping spot, use a hydrocolloid disc from where to buy hydrocolloid patches.
More notes sit in all guides. If you are still deciding whether to open a cone at all, use hydrocolloid vs microdart.