Self-opening stay top opening describes a Sugatsune America HDS-20S/SL-BL lid support designed for top-opening flap doors, so the door can lift and hold using a predictable motion. This S-Type, left-hand stay is built for heavy duty use in lid support applications where the flap opens upward. The product is classified under lid supports and stays, which defines its role as the main control for how the flap moves and holds. The design works specifically with top-opening flap doors, so it fits work surfaces, tables, or cabinets using that motion style. Because it is a self-opening stay, the lid will move past the free stop angle by itself, which reduces effort once the door is released. The stay is made from heavy duty plastic and steel in a black finish, which creates a sturdy operating mechanism with a consistent appearance.
This self-opening stay is used with piano, butt, or concealed hinges, so it works alongside standard hinge types that carry the flap on its pivot line. Using it with piano hinges spreads the load across the door edge, while the stay manages the opening and holding function for the flap. When used with butt hinges, the stay adds controlled motion to a traditional hinge layout. With concealed hinges, the stay supports a cleaner exterior look while still providing the opening and holding action. Because the product is used in pairs, both stays share the load as the door opens and reaches the holding position. The torque performance is defined per pair, so both units together create the stated support on the flap.
This Sugatsune lid support is intended for top-opening flap doors, so it fits applications like upward-swinging work surface covers, table lids, or similar flap doors. It belongs to the lid supports and stays product class, which means it does the job of controlling lid motion rather than hinging alone. The S-Type torque range is 111 to 150 kgf.cm, or 96 to 130 lbs. inch per pair, so it fits doors whose height and weight produce torque within that band when using the specified calculation. The torque calculation given as torque equals door height times one-half times door weight provides a direct way to match the door design to the stay capability. Because it is used with piano, butt, or concealed hinges, it integrates into common cabinet and furniture hinge layouts without changing the hinge type already chosen for the project.
The HDS-20S is designed to hold the door in the fully opened position, so once the flap reaches its end position it stays put while work continues under or around the opening. The self-opening action takes the door past the free stop angle on its own, which means once the door begins to open, the stay assists the rest of the travel. The torque range of 111 to 150 kgf.cm, or 96 to 130 lbs. inch per pair, defines how much door height and weight the pair can support, so doors within that range will open and hold as intended. The torque calculation of door height times one-half times door weight allows direct planning of flap size and material choice around the stay capacity. Because the stay is heavy duty plastic and steel in black, the operating components have a solid mechanical base with a neutral dark look that coordinates with many hinge and cabinet finishes.
The HDS-20S/SL-BL stay is designed for top-opening flap doors, so it supports lids that pivot upward on piano, butt, or concealed hinges.
The self-opening function moves the lid past the free stop angle, so once opening begins the stay helps carry the door to its fully opened position.
This S-Type stay handles 111 to 150 kgf.cm, or 96 to 130 lbs. inch per pair, so flap designs should match that torque range for proper operation.
Torque for the flap is calculated as door height times one-half times door weight, so that value can be compared to the S-Type torque range.
With piano hinges, this stay adds controlled self-opening and holding, while the hinge carries the full-length pivot along the door edge.
The HDS-20S/SL-BL is a left-hand stay used in pairs, so one side of the opening uses this part number to balance the system.
This Sugatsune HDS-20S/SL-BL self-opening stay serves top-opening flap doors using piano, butt, or concealed hinges, so it suits upward-swinging lids that need assisted opening and a defined hold-open position. The S-Type torque range of 111 to 150 kgf.cm, or 96 to 130 lbs. inch per pair, ties directly to the flap height and weight through the supplied torque calculation. The heavy duty plastic and steel construction in black gives the mechanism a sturdy operating base with a neutral appearance that fits many cabinet and furniture layouts. For flap door projects that match the torque range and use the supported hinge types, this left-hand stay provides the self-opening and hold-open behavior described.