Product specifications
US standard and metric
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Our charts below gives useful product specifications for Gemini Marine Products.
All cast metal products are made with 316 stainless steel.
Plastic hinges are made with acrylonitrile butadiene styrene (ABS) plastic, fiberglass reinforced, with a 316 stainless steel link.
Whatever question you have, if the answer isn’t here, please call us and we’ll do out best to help. Then you’ll be ready to shop here on this site or via our distributors.
Split and sliding side mounts*
Product | Item # | Tubing size US | Tubing size metric | Component | Component size |
Sliding side mount | GEMSL-78 | 7/8″ | 22mm | Post screw (incl 2 x nylon washers) | M6 x 1.0 thread 20mm length |
Post height | 1¼” (32mm) off tubing | ||||
GEMSL-1 | 1″ | 25mm | Post screw (incl 2 x nylon washers) | M6 x 1.0 thread 20mm length | |
Post height | 1¼” (32mm) off tubing | ||||
GEMSL-125 | 1¼” | 32mm | Post screw (incl 2 x nylon washers) | M8 x 1.25 thread 20mm length | |
Post height | 1” (25mm) off tubing | ||||
Split side mount | GEMSJ-78 | 7/8″ | 22mm | Post screw (incl 2 x nylon washers) | M6 x 1.0 thread 20mm length |
Post height | 1¼” (32mm) off tubing | ||||
Clamp screw w/nut | M6x1.0 thread 20mm hex head cap screw | ||||
GEMSJ-1 | 1″ | 25mm | Post screw (incl 2 x nylon washers) | M6 x 1.0 thread 20mm length | |
Post height | 1¼” (32mm) off tubing | ||||
Clamp screw w/nut | M6x1.0 thread 20mm hex head cap screw | ||||
GEMSJ-125 | 1¼” | 32mm | Post screw (incl 2 x nylon washers) | M8 x 1.25 thread 20mm length | |
Post height | 1” (25mm) off tubing | ||||
Clamp screw w/nut | M6x1.0 thread 22mm hex head cap screw |
*Screws manufactured in metric
Concave fork and post mounts
All sizes: Post height is 1¼” (32mm) off tubing.
Hinge specifications
Item # | OD standard | OD metric* | Insert diameter standard wall thickness | Insert diameter metric equivalent |
GEMSSH-78-065SS | 7/8″ | 22mm | .065″ stainless steel | 18.75mm |
GEMSSH-1-065SS | 1″ | 25mm | .065″ stainless steel | 21.75mm |
GEMABSH-78049SS | 7/8″ | 22mm | .049″ stainless steel | 18.6mm |
GEMABSH-78058AL | 7/8″ | 22mm | .058″ aluminum | 19mm |
GEMABSH-78065SS | 7/8″ | 22mm | .065″ stainless steel | 19.3mm |
GEMABSH-01065SS | 1″ | 25mm | .065″ stainless steel | 21.8mm |
*Hinge outside diameter manufactured in metric

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