Pro-level On-Stage Stands deluxe heavy-duty double-X keyboard stand is built with 2 tiers and styled for demanding musicians. Super heavy-duty tubing and welded construction support 395 lbs. on the bottom tier. Frame allows height adjustment from 27 to 39 and width adjustment from 11 to 30 . The second tier supports 75 lbs. Uses ERGO-LOK technology for ease of use. The ERGO-LOK system includes an ergonomic trigger an internal rod mechanism and a solid steel spring-loaded deadbolt assembly. Uses dual sheer disk plates and heavy-duty deadbolt for superior stability. Assembling the 2 pieces: 1. Remove upper rear end caps from keyboard stand. 2. Take 2nd tier assembly and slide inner retainer into upper tube of stand. 3. Once second tier retainer is fully inside tube then fully tighten 2 round OSS knobs.