Chaiin of hardware stores located in the various Poligonos, offering a very good range of tools, fastenings, general hardware and PPE. There is a branch in Son Castello, Can Valero and Son Bugadelles
There are two Leroy Merlin DIY stores in Palma, on the Via Cintura (ring road) at the Valdemossa exit (5B) and on the Alcudia highway at Mataraxi. Both stores hold all the usual DIY supplies and are a good source for tools and fittings at a reasonable price.
Poligono Can Valero, Son Bugadelles and Son Castello
A good number of hardware stores can be found in these three industrial areas just on the other side of the Via Cintura, about 20 minutes away from the harbour. Most things can be found here, although it can take quite some time to locate the appropriate shop for a specific Item, especially for non-Spanish speakers.
It is sometimes easier to use one of the part sourcing companies or mobile chandlers to find what you require.
A very large hardware store, selling specialized plumbing supplies (such as weldable plastics etc.) as well as general electrical wares. They also sell components for air conditioning and heating systems. Classic hardware store products are also available. Their website is translated into English.