You are looking for a clip-lock box, covered in camo tape. It's large enough for swaps & TBs. This old farm trail, now a singletrack path, is fairly easy to walk on - but keep an eye out for fallen trees if you're on a bike. If mountain biking is your thing, there are some nice downhill trails in these woods if you know where to look. The cache is placed in woodland managed by Natural Resources Wales (formerly Forestry Commission Wales) with their permission. See the agreement in the UK Geocaching Policies Wiki.