This is a modified Captains of Crush (CoC) No. 4 gripper, with the handles removed and adjusted to allow for load adjustment. The hardness can be changed by adjusting the position of the handles. As shown in the photos, the handles can be removed. When the handles are fixed at the top, the gripper has its original hardness, but the load decreases by moving the handles downwards. Attach the handles to your preferred position and tighten the screws with a hex wrench to complete. You can fix the spring with the two screws anywhere, but to make it easy to adjust, I marked the spring legs at 5mm, 10mm, 15mm, and 20mm from the top (tolerance is +-0.5mm). Considering RGC, the No. 4 rating drops by about 16lb every 5mm. I haven't used it other than for modification and 15 test closes, but it is a used item. As shown in the photos, there are some scratches on the handles. Please judge the condition based on the many photos I took. Everything in the photos is included (a hex wrench is included). I have returned the gripper to its original packaging to prevent the spring from rusting as much as possible. Thank you. #gripper #coc #handgrip #gripper #gripstrength #forearm