Pentom Supply offers replacement rubber tracks for Unic Spydercrane mini crawlers and mini cranes. Many of the Spydercrane models come with optional width rubber tracks. Please verify your width. If you have frequent indoor use we do offer a non marking rubber compound that prevents rubber skid marks in sensitive areas. We do not stock the non marking rubber tracks so they have to be custom ordered with roughly ninety days production time. Please let us know if you have any questions on the various width and tread pattern options for your Spydercrane.