thanks for finding this all out mate.https://www.shippo.co.uk/faqs/what-duties-and-taxes-will-i-have-to-pay/#Duty_and_VAT_Estimator
@MrDJ if that is correct , 37 quids worth of coils plus 23 quid delivery would attract 28 quids worth of duty. So at worst it would be 65 packs of coils for 88 quid if declared correctly
Mine would be 22 quid of goods 20 quid delivery plus 18 quid duty , sixty quid total for twenty packs of coils and two tanks still not a bad deal if declared correctly.