Fragrance gel. SmellyJelly has been formulated to provide a pleasant scent in fan convectors and cassette units. SmellyJelly is easy to apply and is simply placed in the unit, preferably as close to the discharge point as possible. When in place and the unit is turned on, the scent becomes immediately noticeable. SmellyJelly gel blocks now survive even at higher temperatures (up to 70°C) inside a fan convector or cassette unit, providing an even better scent for longer.