There is some sort of pun going on here that is a little beyond my proficiency level to understand. The title and Koyomi's 2nd bubble in frame 2 are pronounced "Sōsai", similar to the name of their product line but the meaning is something akin to offsetting, cancelling, or counterbalancing. Individually the kanji seem to mean "phase" and "kill" or something to that effect. I have some guesses, but I am not positive on how the pun is being played out.
The gear that Madoka is wielding consists of accessories produced for a different Kotobukiya product line, the "Modeling Support Goods" equipment that is compatible with their "Frame Arms" and "Hexa Gear" figures/models. I think the Sousai Shoujo figures are designed to be compatible with the character heads of the Frame Arms Girl figures and can accommodate some of the same accessories. The shield is this product: https://en.kotobukiya.co.jp/product/product-0000001718/ "WEAPON UNIT 35 ENERGY SHIELD" The accessories can often be put together in a variety of ways and mixed together, and the lance seems to be some variation of this product: https://en.kotobukiya.co.jp/product/product-0000003188/ "WEAPON UNIT 08 BATTLE LANCE"
Sousai Shoujo Activity DiaryThe strongest lance and the strongest shield!Here's what I want to say---Ah-!Shhh, Koyomi!