These are climbing accessories for creating multiple anchor points and organizing the work area. The material is aluminum alloy, and it has been anodized. The strength is 35kN (kilonewtons). The hole diameters are 27mm for the large hole and 20mm for the small hole. The dimensions are 81mm x 90mm, and the thickness is 7.5mm. Used a few times, it seems to be used for fixing branches etc. in several places. Thank you for viewing.