Top tube adaptor

A top tube adaptor comprising:

• a body, two fixers connected with two ends of the body respectively, and a slidable rod fitted with one of the two fixers;
• wherein the body includes at least one slot defined on an outer wall thereof and configured to accommodate at least one positioning rack, and a respective positioning rack has multiple teeth;
• wherein the slidable rod includes a channel configured to slide the slidable rod along the body, and the slidable rod includes a locking seat rotatably connected with an end of the slidable rod and accommodating a rotatable connector, wherein the rotatable connector includes two shafts rotatably connected with two sides of a middle section of the rotatable connector respectively, a press portion extending from a first end of the rotatable connector, a button extending from the press portion, an orientation segment extending into the at least one slot from a second end of the rotatable connector, an engagement portion formed on an inner side of the orientation segment and retained with one of the multiple teeth, and a first resilient element abutting against an inner side of the orientation segment and fixed in the locking seat;
• wherein a respective fixer includes a curved hook extending from an end thereof, a cutout defined between the end of the respective fixer and the curved hook, two tabs located beside the cutout away from the curved hook, a coupling projection rotatably connected with the two tabs and closing the cutout, a column inserted through the two tabs, and a second resilient element fitted on the column, wherein the second resilient element has two abutting segments, one of the two abutting segments abuts against the two tabs, and the other abutting segment contacts with or removes from the coupling projection so as to close or open the cutout;
• and
• wherein the two fixers are connected with two ends of the slidable rod respectively.