It uses the classic 0.100" (2.54mm) pitch on both rows and between rows — a standard that matches breadboard grids and legacy 0.1"-spaced prototyping boards. All 10 positions are loaded with square male pins in a 2x5 arrangement, terminated through-hole with solder tails 0.120" (3.05mm) long. The UL94 V-0 black housing and phosphor bronze contacts round out a straightforward, field-proven interconnect.
Typical use is stacking two PCBs at a right angle or parallel with a separate socket, or as a pin strip for a wire-to-board IDC connector. The 0.410" (10.41mm) overall contact length gives enough standoff for most mezzanine or interposer applications.
Comparison: 79425-410HLF vs 79425-410BLF
The 79425-410BLF shares the same BERGSTIK II series, 10 positions, dual-row 0.100" (2.54mm) pitch, and tin-plated contacts. The difference is in the solder tail length: the 410HLF has a 0.120" (3.05mm) post, while the 410BLF carries a longer post. If your board thickness or through-hole depth requires a longer tail for solder fillet, the BLF variant is the one to check — otherwise the HLF is the standard drop-in.