More than 50 items were taken overnight between Sunday August 7 and Monday August 8 from premises at the Whitburn Road industrial estate in Bathgate.
Police are appealing for anyone with information about the theft to come forward.
The items were worth a five-figure sum, and included several battery packs and chargers, gas powered tools and drills.
Pc Michelle Robertson said: “This is a high-value theft which has deprived the owners of this business of thousands of pounds worth of tools and materials.
“We are eager to trace those responsible.”
Police Scotland can be contacted on 101 or anonymously through Crimestoppers