The GL-1U grab has a modified axle design: now, instead of welded ones, one-piece axles are manufactured. Jumpers have been introduced into the design of the traverse, increasing the rigidity of the lugs for attaching the petals. The diameter of the piston rod of the petal opening hydraulic cylinders has been increased from 35 to 40 mm. Bushings made of composite materials (PAP) have been introduced instead of steel bushings.
The design of the petal itself has undergone the greatest changes - instead of a cheek of 2 parts, a single part made of S700MS steel was introduced, which made it possible to increase the strength of the petal by 1.5 times. Tests on the new grapple have shown that the design changes have increased the safety margin for each petal to 5 tonnes.