Given a bunch of diving lights... tax on selling them?

Hi! I’ve been given a box of diving lights and had a quick question about tax - will I incur any if I sell them off? I’ll probably keep a few for spares but will sell most of them. I’ve had a look at this tax calculator and it says I’m almost paying 40% tax. Will I pay that on the lights if they do sell? Thanks in advance :wink: