Blum 21" TANDEM+ BLUMOTION 5/8" Runner

The Blum 21” TANDEM+ BLUMOTION runner delivers 100-pound static load capacity with integrated soft-close in a concealed undermount design. Cabinet installers get four-dimensional adjustment — height, side-to-side, tilt, and depth — for dialing in perfect drawer alignment. These slides target custom cabinetmakers and kitchen remodelers who need heavy-duty performance with precise adjustability.

Model 563H5330B works specifically with 1/2 to 5/8 inch drawer thickness. Contractors working with thicker drawer boxes need the 563F series instead.

Load Capacity and Construction Details

The zinc-plated steel construction handles real-world cabinet loads without sagging or binding. Testing confirms these numbers:

Specification	Value	Source
Static Load Capacity	100 lbs	manufacturer
Dynamic Load Capacity	90-100 lbs	manufacturer
Material	Zinc-plated steel	manufacturer
Weight	6.2 lbs per pair	manufacturer
Overall Length	21-9/16 inches	manufacturer
Extension Type	Full extension	manufacturer

100 pounds static capacity means these slides handle cast iron cookware drawers, small appliance storage, and heavy utensil collections without deflection. The zinc plating resists corrosion in Montana’s temperature swings — important when humidity drops below 20% in winter then spikes during spring snowmelt.

Full extension means complete drawer access. No reaching into dark corners or fighting partial-extension slides that hide the back third of the drawer.

Installation Requirements and Compatibility

Drawer side thickness must be 1/2” to 5/8”. Rear mounting bracket required for face-frame cabinets. Specific drill templates (e.g., T65.1600.01) recommended for precision.

The slides don’t include everything needed for installation. Required components sold separately:

Component	Options	Purpose
Front Locking Devices	T51.1801 (Standard) T51.1901 (Side-adjustable) T51.1901.PS (Depth-adjustable)	Secure drawer to slides
Rear Brackets	295.3750 (Screw-on) 295.3750.01 (Narrow) Dowel-mount sockets	Face-frame mounting
Screws	#6 x 5/8” Pozi or Phillips flat head	All mounting points

Elongated holes for depth adjustment solve the alignment headaches that plague fixed-position slides. When face frames aren’t perfectly square or drawer boxes vary slightly, these adjustment features save callbacks.

The four-dimensional adjustment works through the front locking devices and slide mechanisms. Height, side-to-side, tilt, and depth adjustments happen after installation — no removing and remounting slides to fix alignment issues.

The Bottom Line

Everything went perfectly. Order, delivery and communication were orderly and efficient. That 4.7-star rating across 285 reviews backs up what contractors already know — Blum hardware works.

These slides excel in custom kitchen builds where drawer loads exceed standard residential use. The 100-pound capacity handles Montana’s outdoor gear storage needs — think heavy cast iron, canning equipment, or workshop drawers loaded with hand tools. ISO 9001 (Blum Corporate), ISO 14001 (Blum Corporate) certifications confirm consistent manufacturing quality.

Skip these for budget builds or standard bathroom vanities where 75-pound slides cost half as much. The premium makes sense for kitchens taking daily abuse or custom furniture meant to last decades.

Covers defects in materials and workmanship for the original homeowner/purchaser. If hardware is obsolete or discontinued, Blum reserves the right to replace with a current offering; no guarantee of interchangeability. That lifetime warranty comes with typical restrictions, but Blum’s track record suggests they’ll be making compatible hardware for years to come.

Frequently Asked Questions

Q: What’s the difference between 563H and 563F series?

563H for standard 5/8” or thinner sides. Designed for thicker drawer sides (5/8” to 3/4”). Measure drawer thickness before ordering — using the wrong series means the slides won’t fit.

Q: Do these slides include mounting hardware?

No. The slides come as a left/right pair only. Front locking devices, mounting screws, and rear brackets for face-frame cabinets must be ordered separately.

Q: Can these handle heavy cookware drawers?

Yes. The 100-pound static load rating handles cast iron collections, stand mixers, and heavy pot drawers. Dynamic rating of 90-100 pounds covers normal use.

Q: How does the soft-close mechanism hold up in cold weather?

The BLUMOTION mechanism uses steel springs and dampers, not temperature-sensitive hydraulics. Works reliably in unheated Montana garages and shops.

Q: What drawer box construction works best with these slides?

Any solid construction from 1/2 to 5/8 inch thickness. Dovetail, doweled, or quality plywood boxes all work. The slides mount to the bottom of the drawer, not the sides.