With the Tente R47-36-40 expander fitting, you can mount caster wheels securely and easily into square tubing. Without any need for welding or tapping threads, you create a firm connection inside hollow profiles with an internal dimension of 36 to 40 mm. The combination of a durable steel core and a synthetic body expands evenly upon tightening, locking the assembly firmly in place. This provides a rattle-free, vibration-resistant fit that prevents rotation. It is the practical choice for building, retrofitting, and maintaining workshop trolleys, mobile carts, and tubular furniture.