What is the difference between side mount and undermount drawer slides?

Side mount slides fix to the drawer sides and cabinet walls — easy to fit and tolerant of cabinet tolerances. Undermount slides sit beneath the drawer box, hide the hardware for a cleaner look, and need a compatible drawer box with the right reveal. AOLISHENG builds both: side-mount heavy-duty series (2053 / 2576 / 7625) and undermount soft-close series (MK316 / U4510K).

What does full extension mean compared with 3/4 extension?

3/4 extension leaves the back of the drawer still inside the cabinet; full extension brings the whole drawer clear of the cabinet face so you can reach the back corner. Most AOLISHENG heavy-duty and soft-close series are full extension.

How do I choose the load rating for a drawer slide?

Add the heaviest realistic contents, then add 25–30% headroom so the slide is not run at 100% of its rating every day. AOLISHENG ratings run from 100 lb (U1245) through 265 lb (2053 family), 330 lb (2071), 500 lb (2576 family) up to 770 lb (AQ7625K3 twin-slide).

What are soft-close drawer slides and when do I need them?

Soft-close slides use a damper that pulls the drawer shut in the last few centimetres, preventing slamming. They are most noticeable on kitchen and bathroom cabinetry and also reduce the shock load that gradually loosens a carcass. AOLISHENG soft-close options include K2053, U4510K and MK316.

Are stainless steel slides worth it for outdoor or marine use?

Yes — whenever the slide is exposed to weather, salt air, humidity or frequent wash-down (outdoor kitchens, marine galleys, food-prep, coastal installs). AOLISHENG stainless options include W2053, W2576, W5115 and U4510K.

Which AOLISHENG series number maps to which spec?

The stamped codes read: 1245 = 100 lb stainless side mount; 4510 = 100 lb stainless; 5115 = 150 lb; 2053 = 265 lb; 2071 = 330 lb; 2576 = 500 lb; 7625 = 770 lb twin-slide. Remove the drawer and read the code on the inner rail, or send a photo and AOLISHENG will match it.

Can heavy-duty slides be used in RVs, trucks and vehicles?

Yes, with a locking slide so the drawer cannot slide open under braking or cornering. Use locking series such as D5115, D2053 or D7625 for any moving-vehicle storage.

Drawer Slide Guides, Household

Undermount Drawer Slides: The Hidden Hardware Behind a Premium Cabinet Look

Posted by

Aolisheng

September 13, 2026

On September 13, 2026

What Are Undermount Drawer Slides?

Undermount (or under-mount) drawer slides are mounted beneath the drawer box, hidden from view when the drawer is closed. Unlike side-mount slides that attach to the drawer sides, undermounts attach to the bottom edges and run along the cabinet’s interior walls. The result is the clean, hardware-free look you see in high-end kitchen and bathroom cabinetry.

Undermount vs Side-Mount — Quick Comparison

	Undermount	Side-mount
Visible hardware	None — fully hidden	Visible on drawer sides
Drawer width	Slightly narrower (rails sit inside)	Full drawer width
Side clearance	~1/2″ (13 mm) each side	~1/2″ (13 mm) each side
Load capacity	Typically 75–100 lb	Up to 500 lb+ (heavy-duty)
Soft-close	Almost always integrated	Optional
Install difficulty	Higher (needs precision)	Easy

When to Choose Undermount

Premium kitchen & bath cabinets — the invisible look is the selling point.
Full-extension access — most undermounts are full-extension so you reach the back.
Soft-close as standard — no slamming, quieter rooms.

Clearance & Installation Rules

Leave 1/2″ (13 mm) clearance on each side of the drawer between the box and the cabinet wall.
The drawer bottom must be thick enough to anchor the slide brackets (18 mm plywood is ideal).
Use the manufacturer’s jig or measure twice — undermounts are unforgiving of misalignment.
Confirm the slide length matches the cabinet depth, not the drawer front.

AOLISHENG Undermount Option

Our MK316 80 lb Undermount Soft-Close Slides deliver a concealed, full-extension, soft-close motion in a 2-pair pack sized for standard kitchen cabinets. For heavier or side-mounted builds, see our side-mount drawer slides or the drawer slide selection chart.

Need help sizing an undermount for a custom cabinet? Contact our engineers with your drawer dimensions.